Structural determinants of high-affinity binding of ryanoids to the vertebrate skeletal muscle ryanodine receptor: a comparative molecular field analysis.
Ryanodine binds to specific membrane proteins, altering the calcium permeability of intracellular membranes. In this study 19 ryanoids were isolated or synthesized and the structures correlated to the strength of binding to vertebrate skeletal muscle ryanodine receptors. Global minima were determined by employment of molecular mechanics and dynamics augmented by ... More
Ryanodine receptor of skeletal muscle is a gap junction-type channel.
AuthorsMa J, Fill M, Knudson CM, Campbell KP, Coronado R
JournalScience
PubMed ID2459777
In the sarcoplasmic reticulum membrane of skeletal muscle, the ryanodine receptor forms an aqueous pore identified as the calcium-release pathway that operates during excitation-contraction coupling. The purified ryanodine receptor channel has now been shown to have four properties usually associated with gap junction channels: (i) a large nonspecific voltage-dependent conductance ... More
Evidence for the existence of inositol (1,4,5)-trisphosphate- and ryanodine-sensitive pools in bovine endothelial cells. Ca2+ releases in cells with different basal level of intracellular Ca2+.
AuthorsMozhayeva MG, Mozhayeva GN
JournalPflugers Arch
PubMed ID8764961
'In single bovine aortic endothelial (BAE) cells pre-loaded with Fura-2, Ca2+ transients in a Ca2+-free medium have been revealed, which evidently reflects Ca2+ release from intracellular stores. In cells with different levels of resting basal cytoplasmic Ca2+ ([Ca2+]i) from about 50 to 110 nM, a biphasic dependence of the Ca2+ ... More
Different triggers for calcium oscillations in mouse eggs involve a ryanodine-sensitive calcium store.
AuthorsSwann K
JournalBiochem J
PubMed ID1417794
'Relative intracellular free Ca2+ concentrations ([Ca2+]i) were monitored in mature unfertilized mouse eggs by measuring fluorescence of intracellular fluo3. A number of different agents were found to cause sustained repetitive transient [Ca2+]i oscillations. These were microinjection of a cytosolic sperm factor, sustained injection of Ins-(1,4,5)P1, or extracellular addition of the ... More
Calcium signalling in granule neurones studied in cerebellar slices.
AuthorsKirischuk S, Voitenko N, Kostyuk P, Verkhratsky A
JournalCell Calcium
PubMed ID8653756
'The cytoplasmic free calcium concentration ([Ca2+]i) was studied in Fura-2/AM loaded granule neurones in acutely prepared cerebellar slices isolated from neonatal (6 days old) and adult (30 days old) mice. Bath application of elevated (10-50 mM) KCl-containing extracellular solutions evoked [Ca2+]i rise which was dependent on extracellular Ca2+. The K(+)-induced ... More
Thimerosal potentiates Ca2+ release mediated by both the inositol 1,4,5-trisphosphate and the ryanodine receptors in sea urchin eggs. Implications for mechanistic studies on Ca2+ signaling.
AuthorsTanaka Y, Tashjian AH
JournalJ Biol Chem
PubMed ID8157654
'Two intracellular Ca2+ release pathways are modulated by Ca2+ itself, namely Ca(2+)-induced Ca2+ release (classical CICR), and Ca(2+)-sensitized inositol 1,4,5-trisphosphate (InsP3)-induced Ca2+ release (CSIICR). Both of these pathways are thought to be important in generating cytosolic Ca2+ oscillations. Caffeine and the sulfhydryl reagent thimerosal (TMS) are frequently used as selective ... More
Oscillation of cytoplasmic free calcium concentration induced by insulin-like growth factor I.
AuthorsKojima I, Mogami H, Ogata E
JournalAm J Physiol
PubMed ID1550224
'The effect of insulin-like growth factor I (IGF-I) on cytoplasmic free calcium concentration ([Ca2+]c) was studied in single BALB/c 3T3 cells by monitoring fura-2 fluorescence. In primed competent cells, IGF-I (1 nM) increased [Ca2+]c in approximately 60% of the cells tested. IGF-I-mediated elevation of [Ca2+]c was observed after a 4- ... More
Characterization of a plasma membrane calcium oscillator in rat pituitary somatotrophs.
AuthorsTomic M, Koshimizu T, Yuan D, Andric SA, Zivadinovic D, Stojilkovic SS
JournalJ Biol Chem
PubMed ID10585449
'In excitable cells, oscillations in intracellular free calcium concentrations ([Ca(2+)](i)) can arise from action-potential-driven Ca(2+) influx, and such signals can have either a localized or global form, depending on the coupling of voltage-gated Ca(2+) influx to intracellular Ca(2+) release pathway. Here we show that rat pituitary somatotrophs generate spontaneous [Ca(2+)](i) ... More
Localization of Ca2+ release channels with ryanodine in junctional terminal cisternae of sarcoplasmic reticulum of fast skeletal muscle.
AuthorsFleischer S, Ogunbunmi EM, Dixon MC, Fleer EA
JournalProc Natl Acad Sci U S A
PubMed ID2414773
'The mechanism of Ca2+ release from sarcoplasmic reticulum, which triggers contraction in skeletal muscle, remains the key unresolved problem in excitation-contraction coupling. Recently, we have described the isolation of purified fractions referable to terminal and longitudinal cisternae of sarcoplasmic reticulum. Junctional terminal cisternae are distinct in that they have a ... More
Increased internal Ca2+ mediates neural induction in the amphibian embryo.
AuthorsMoreau M, Leclerc C, Gualandris-Parisot L, Duprat AM
JournalProc Natl Acad Sci U S A
PubMed ID7809092
'The molecular mechanism of neural induction is still unknown and the identity of the natural inducer remains elusive. It has been suggested that both the protein kinase C and cAMP signal transduction pathways may be involved in mediating its action. Here we provide evidence that Ca2+ is implicated in the ... More
Different localization of inositol 1,4,5-trisphosphate and ryanodine binding sites in rat liver.
AuthorsFeng L, Pereira B, Kraus-Friedmann N
JournalCell Calcium
PubMed ID1321686
'The distribution of inositol 1,4,5-trisphosphate and ryanodine binding sites between plasma membrane, microsomal, and mitochondrial fractions of rat liver were compared. IP3 bound mostly to the plasma membrane fraction (Kd = 6 nM; Bmax = 802 fmol/mg protein). Some IP3 binding sites were also present in the microsomal and mitochondrial ... More
Ca(2+) signals mediated by Ins(1,4,5)P(3)-gated channels in rat ureteric myocytes.
'Localized Ca(2+)-release signals (puffs) and propagated Ca(2+) waves were characterized in rat ureteric myocytes by confocal microscopy. Ca(2+) puffs were evoked by photorelease of low concentrations of Ins(1,4,5)P(3) from a caged precursor and by low concentrations of acetylcholine; they were also observed spontaneously in Ca(2+)-overloaded myocytes. Ca(2+) puffs showed some ... More
Effects of halothane on sarcoplasmic reticulum calcium release channels in porcine airway smooth muscle cells.
AuthorsPabelick CM, Prakash YS, Kannan MS, Warner DO, Sieck GC
JournalAnesthesiology
PubMed ID11465560
'BACKGROUND: Volatile anesthetics relax airway smooth muscle (ASM) by altering intracellular Ca2+ concentration ([Ca2+]i). The authors hypothesized that relaxation is produced by decreasing sarcoplasmic reticulum Ca2+ content via increased Ca2+ "leak" through both inositol trisphosphate (IP3) and ryanodine receptor channels. METHODS: Enzymatically dissociated porcine ASM cells were exposed to acetylcholine ... More
Mitochondrial Ca2+ uptake regulates the excitability of myenteric neurons.
AuthorsVanden Berghe P, Kenyon JL, Smith TK
JournalJ Neurosci
PubMed ID12177194
'We investigated the role of mitochondria in the regulation of intracellular Ca2+ ([Ca2+]i) and excitability of myenteric neurons in guinea pig ileum, using microelectrodes and fura-2 [Ca2+]i measurements. In AH/Type-II neurons, action potentials evoke ryanodine-sensitive increases in [Ca2+]i that activate Ca2+-dependent K+ channels and slow afterhyperpolarizations (AH) lasting approximately 15 ... More
The sperm-induced Ca2+ wave following fertilization of the Xenopus egg requires the production of Ins(1, 4, 5)P3.
AuthorsNuccitelli R, Yim DL, Smart T
JournalDev Biol
PubMed ID7687224
'We used fluorescence ratio imaging of fura-2 in the egg of Xenopus laevis to study the initiation and propagation of the wave of increased free Ca2+ that is normally triggered at fertilization. Naturally matured, jellied eggs were injected with fura-2 and ratio-imaged with fluorescence excitation at 350 and 385 nm ... More
Modulation of Ca2+ release in cultured neonatal rat cardiac myocytes. Insight from subcellular release patterns revealed by confocal microscopy.
AuthorsLipp P, Niggli E
JournalCirc Res
PubMed ID8156645
'It is well established that in heart muscle the influx of Ca2+ through Ca2+ channels during the action potential is the main trigger for Ca2+ release from the sarcoplasmic reticulum (SR), but intact cardiac tissue and single myocytes are also known to exhibit spontaneous Ca2+ release from the SR under ... More
Ryanodine sensitizes the Ca(2+) release channel (ryanodine receptor) to Ca(2+) activation.
AuthorsMasumiya H, Li P, Zhang L, Chen SR
JournalJ Biol Chem
PubMed ID11507100
'Ryanodine, a plant alkaloid, is one of the most widely used pharmacological probes for intracellular Ca(2+) signaling in a variety of muscle and non-muscle cells. Upon binding to the Ca(2+) release channel (ryanodine receptor), ryanodine causes two major changes in the channel: a reduction in single-channel conductance and a marked ... More
Effect of ryanodine on cardiac calcium current and calcium channel gating current.
AuthorsLacampagne A, Caputo C, Argibay J
JournalBiophys J
PubMed ID8770213
'The effects of 100 microM ryanodine on the L-type calcium channel were studied using the pacth-clamp technique in isolated guinea pig ventricular myocytes. The inactivation kinetics of the calcium current were slowed down in the presence of ryanodine in agreement with the blockade of the release of calcium from the ... More
Effects of ryanodine in skinned cardiac cells.
AuthorsFabiato A
JournalFed Proc
PubMed ID2415405
'Ryanodine (1 X 10(-5) M) did not affect the Ca2+ sensitivity of the myofilaments of skinned (sarcolemma removed by microdissection) cardiac cells from the rat ventricle. Ryanodine (1 X 10(-5) M) inhibited three types of Ca2+ release from the sarcoplasmic reticulum (SR), which have different mechanisms: 1) Ca2+-induced release of ... More
Ryanodine block of calcium oscillations in heart muscle and the sodium-tension relationship.
AuthorsCannell MB, Vaughan-Jones RD, Lederer WJ
JournalFed Proc
PubMed ID2998887
'The control of tension is examined in cardiac Purkinje fibers. We show, in accordance with earlier results (14, 15), that tension produced by this preparation is a steep power function of intracellular sodium. With the aid of ryanodine, a pharmacological agent that blocks spontaneous and spatially asynchronous calcium release from ... More
Ryanodine modifies conductance and gating behavior of single Ca2+ release channel.
AuthorsRousseau E, Smith JS, Meissner G
JournalAm J Physiol
PubMed ID2443015
'Ryanodine affects excitation-contraction coupling in skeletal and cardiac muscle by specifically interacting with the sarcoplasmic reticulum (SR) Ca2+ release channel. The effect of the drug at the single channel level was studied by incorporating skeletal and cardiac SR vesicles into planar lipid bilayers. The two channels were activated by micromolar ... More
In situ characterization of nonmitochondrial Ca2+ stores in individual pancreatic beta-cells.
AuthorsTengholm A, Hagman C, Gylfe E, Hellman B
JournalDiabetes
PubMed ID9703321
'Free Ca2+ was measured in intracellular stores of individual mouse pancreatic beta-cells using dual-wavelength microfluorometry and the low-affinity Ca2+ indicator furaptra. Controlled permeabilization of the plasma membrane with 4 micromol/l digitonin revealed that 22% of the furaptra was trapped in intracellular nonnuclear compartments. When 3 mmol/l ATP and 200 nmol/l ... More
cGMP mobilizes intracellular Ca2+ in sea urchin eggs by stimulating cyclic ADP-ribose synthesis.
AuthorsGalione A, White A, Willmott N, Turner M, Potter BV, Watson SP
JournalNature
PubMed ID7692303
'Many hormones or neurotransmitters act at cell surface receptors to increase the intracellular free calcium concentration, triggering a wide range of cellular responses. As the source of this Ca2+ is often internal stores, additional messengers are required to convey the hormonal message from the plasma membrane. Cyclic ADP-ribose (cADPR) has ... More
Calcium in sympathetic varicosities of mouse vas deferens during facilitation, augmentation and autoinhibition.
AuthorsBrain KL, Bennett MR
JournalJ Physiol
PubMed ID9279805
'1. The sympathetic nerve terminals of the mouse vas deferens were loaded with the calcium indicator Oregon Green 488 BAPTA-1 by orthograde transport along the postganglionic nerves. Changes in the calcium concentration in the varicosity (delta [Ca2+]v) were determined following single impulses, and short (5-impulse) and long (200-impulse) trains at ... More
High affinity C10-Oeq ester derivatives of ryanodine. Activator-selective agonists of the sarcoplasmic reticulum calcium release channel.
'The plant alkaloids ryanodine and dehydroryanodine are specific and potent modulators of the sarcoplasmic reticulum calcium release channel. In the present study, acidic, basic, and neutral side chains esters of these diterpene compounds were prepared and their pharmacologic activities were assessed. Binding affinities of the novel C10-Oeq ester derivatives for ... More
'The Ca2+-dependent ryanodine binding site of rabbit cardiac sarcoplasmic reticulum is solubilized by treatment with 20 mM CHAPS detergent and 1 M NaCl for 30 min at 0 degrees C. Ca2+ added at 5 microM enhances binding, at 0.5 mM increases both the affinity and number of [3H]ryanodine binding sites, ... More
Multiple effects of ryanodine on intracellular free Ca2+ in smooth muscle cells from bovine and porcine coronary artery: modulation of sarcoplasmic reticulum function.
AuthorsWagner-Mann C, Hu Q, Sturek M
JournalBr J Pharmacol
PubMed ID1504718
'1. The effects of ryanodine and caffeine on intracellular free Ca2+ concentration ([Ca2+]i) were studied by use of fura-2 microfluorometry in single smooth muscle cells freshly dispersed from bovine and porcine coronary artery. 2. Bovine and porcine cells demonstrated similar sensitivities to 10 min of exposure to ryanodine in physiological ... More
Calcium signaling mechanisms in dedifferentiated cardiac myocytes: comparison with neonatal and adult cardiomyocytes.
AuthorsPoindexter BJ, Smith JR, Buja LM, Bick RJ
JournalCell Calcium
PubMed ID11728132
'Our studies focused on calcium sparking and calcium transients in cultured adult rat cardiomyocytes and compared these findings to those in cultured neonatal and freshly isolated adult cardiomyocytes. Using deconvolution fluorescence microscopy and spec trophotometric image capture, sequence acquisitions were examined for calcium spark intensities, calcium concentrations and whether sparks ... More
'In this study, we have identified and partially characterized a mouse T-lymphoma ryanodine receptor on a unique type of internal vesicle which bands at the relatively light density of 1.07 g/ml. Analysis of the binding of [3H]ryanodine to these internal vesicles reveals the presence of a single, low affinity binding ... More
Spontaneous Ca2+ spiking in a vascular smooth muscle cell line is independent of the release of intracellular Ca2+ stores.
AuthorsByron KL, Taylor CW
JournalJ Biol Chem
PubMed ID8463226
'Monolayers of fura-2-loaded A7r5 cells, a cell line derived from rat embryonic aorta, generated spontaneous Ca2+ spikes that were synchronized within the cell population. These Ca2+ spikes were abolished by removal of extracellular Ca2+ or addition of nimodipine (50 nM), and their frequency was increased by depolarization with high K+ ... More
Force, membrane potential, and [Ca2+]i during activation of rat mesenteric small arteries with norepinephrine, potassium, aluminum fluoride, and phorbol ester. Effects of changes in pHi.
AuthorsJensen PE, Hughes A, Boonen HC, Aalkjaer C
JournalCirc Res
PubMed ID8330374
'In activated rat mesenteric small arteries, the effect of pHi on force, membrane potential, and free cytosolic calcium ([Ca2+]i) was assessed. Arteries were mounted in a myograph for isometric force development, and [Ca2+]i, pHi, or membrane potential was measured simultaneously with force. During activation with norepinephrine, potassium, aluminum fluoride (AlF-4), ... More
Nitric oxide-induced mobilization of intracellular calcium via the cyclic ADP-ribose signaling pathway.
AuthorsWillmott N, Sethi JK, Walseth TF, Lee HC, White AM, Galione A
JournalJ Biol Chem
PubMed ID8631983
'Cyclic adenosine diphosphate ribose (cADPR) is a potent endogenous calcium-mobilizing agent synthesized from beta-NAD+ by ADP-ribosyl cyclases in sea urchin eggs and in several mammalian cells (Galione, A., and White, A. (1994) Trends Cell Biol. 4, 431 436). Pharmacological studies suggest that cADPR is an endogenous modulator of Ca2+-induced Ca2+ ... More
Fast axonal transport is modulated by altering trans-axolemmal calcium flux.
AuthorsBreuer AC, Bond M, Atkinson MB
JournalCell Calcium
PubMed ID1586941
'Factors involved in fast axonal transport (motor proteins, microtubules, organelles, etc.) have been identified but the molecular mechanism controlling transport is unknown. We used video enhanced microscopy to directly evaluate the effect of calcium on fast axonal transport (FAxT). FAxT alterations included rapid speed decreases (within minutes) in Ca2+ free ... More
Involvement of Ca2+ waves in excitation-contraction coupling of rat atrial cardiomyocytes.
AuthorsTanaka H, Masumiya H, Sekine T, Kase J, Kawanishi T, Hayakawa T, Miyata S, Sato Y, Nakamura R, Shigenobu K
JournalLife Sci
PubMed ID11833720
'Two-dimensional and line-scan analyses of the early phase Ca2+ transients in rat cardiomyocytes were performed with a rapid-scanning laser confocal microscope and fluo-3 to elucidate the mechanism of activation of Ca2+ release from the sarcoplasmic reticulum in atrial myocytes which lack a well developed T-tubular network. On electrical stimulation of ... More
2-Aminoethoxydiphenyl borate modulates kinetics of intracellular Ca(2+) signals mediated by inositol 1,4,5-trisphosphate-sensitive Ca(2+) stores in single pancreatic acinar cells of mouse.
AuthorsWu J, Kamimura N, Takeo T, Suga S, Wakui M, Maruyama T, Mikoshiba K
JournalMol Pharmacol
PubMed ID11093775
'Regulation of the kinetics of intracellular Ca(2+) signals with a novel, membrane-penetrable, inositol 1,4,5-trisphosphate (InsP(3)) receptor/Ca(2+) channel modulator, 2-amino-ethoxydiphenyl borate (2APB), has been investigated using patch-clamp, whole-cell recording to monitor Ca(2+)-activated Cl(-) currents in single isolated pancreatic acinar cells. 2APB itself fails to evoke a detectable current response but it ... More
Endoplasmic reticulum Ca2+ depletion unmasks a caffeine-induced Ca2+ influx in human aortic endothelial cells.
AuthorsCorda S, Spurgeon HA, Lakatta EG, Capogrossi MC, Ziegelstein RC
JournalCirc Res
PubMed ID7554146
'Intracellular Ca2+ pools contribute to changes in cytosolic [Ca2+] ([Ca2+]i), which play an important role in endothelial cell signaling. Recently, endothelial ryanodine-sensitive Ca2+ stores were shown to regulate agonist-sensitive intracellular Ca2+ pools. Since caffeine binds the ryanodine Ca2+ release channel on the endoplasmic reticulum in a variety of cell types, ... More
Modulation of a voltage-gated calcium channel linked to activation of glutamate receptors and calcium-induced calcium release in the catfish retina.
AuthorsLinn CL, Gafka AC
JournalJ Physiol
PubMed ID11507157
'1. Catfish (Ictalurus punctatus) retinal cone horizontal cells contain an L-type calcium current that has been proposed to be involved in visual processing. Here we report on the modulation of this current by activation of glutamate receptors and calcium-induced calcium release (CICR) from intracellular calcium stores. 2. Fluorescence data obtained ... More
cAMP-dependent mobilization of intracellular Ca2+ stores by activation of ryanodine receptors in pancreatic beta-cells. A Ca2+ signaling system stimulated by the insulinotropic hormone glucagon-like peptide-1-(7-37).
AuthorsHolz GG, Leech CA, Heller RS, Castonguay M, Habener JF
JournalJ Biol Chem
PubMed ID10318832
'Glucagon-like peptide-1 (GLP-1) is an intestinally derived insulinotropic hormone currently under investigation for use as a novel therapeutic agent in the treatment of type 2 diabetes mellitus. In vitro studies of pancreatic islets of Langerhans demonstrated that GLP-1 interacts with specific beta-cell G protein-coupled receptors, thereby facilitating insulin exocytosis by ... More
Spontaneous [Ca2+]i fluctuations in rat chromaffin cells do not require inositol 1,4,5-trisphosphate elevations but are generated by a caffeine- and ryanodine-sensitive intracellular Ca2+ store.
AuthorsMalgaroli A, Fesce R, Meldolesi J
JournalJ Biol Chem
PubMed ID2105938
'A considerable fraction (65%) of single rat chromaffin cells loaded with the fluorescent [Ca2+]i indicator fura-2 exhibited spontaneous rhythmic fluctuations with an average period of approximately 100 s. Parallel patch clamp experiments as well as fura-2 experiments carried out in Ca2(+)-free and other modified media in the presence of Ca2+ ... More
Calcium-induced calcium release in neurones.
AuthorsVerkhratsky A, Shmigol A
JournalCell Calcium
PubMed ID8653752
'Neurones express several subtypes of intracellular Ca2+ channels, which are regulated by cytoplasmic calcium concentration ([Ca2+]c) and provide the pathway for Ca(2+)-induced Ca2+ release (CICR) from endoplasmic reticulum Ca2+ stores. The initial studies of CICR which employed several pharmacological tools (and in particular caffeine and ryanodine) demonstrated that: (i) caffeine ... More
Opposing actions of inositol 1,4,5-trisphosphate and ryanodine receptors on nuclear factor of activated T-cells regulation in smooth muscle.
AuthorsGomez MF, Stevenson AS, Bonev AD, Hill-Eubanks DC, Nelson MT,
JournalJ Biol Chem
PubMed ID12145283
'The nuclear factor of activated T-cells (NFAT), originally identified in T-cells, has since been shown to play a role in mediating Ca(2+)-dependent gene transcription in diverse cell types outside of the immune system. We have previously shown that nuclear accumulation of NFATc3 is induced in ileal smooth muscle by platelet-derived ... More
Role of Ca2+ in induction of neurotransmitter-related gene expression by butyrate.
AuthorsZia MT, Nankova BB, Krishnan K, Gueorguiev VD, Frenz CM, Sabban EL, La Gamma EF
JournalNeuroreport
PubMed ID15129169
'We examined the effect of butyrate on neurotransmitter-related gene expression and calcium homeostasis in PC12 cells. Pretreatment with Ca2+ chelators (EGTA or BAPTA-AM) attenuated the butyrate-triggered accumulation of TH and ppEnk mRNA indicating that Ca2+ plays a role in butyrate-induced regulation of neuronal genes. Butyrate alone did not alter intracellular ... More
Depletion of intracellular Ca2+ by caffeine and ryanodine induces apoptosis of chinese hamster ovary cells transfected with ryanodine receptor.
AuthorsPan Z, Damron D, Nieminen AL, Bhat MB, Ma J
JournalJ Biol Chem
PubMed ID10764805
'Recent studies have suggested a central role for Ca(2+) in the signaling pathway of apoptosis and certain anti-apoptotic effects of Bcl-2 family of proteins have been attributed to changes in intracellular Ca(2+) homeostasis. Here we report that depletion of Ca(2+) from endoplasmic reticulum (ER) leads to apoptosis in Chinese hamster ... More
A procedure for purification of the ryanodine receptor from skeletal muscle.
AuthorsHawkes MJ, Díaz-Muñoz M, Hamilton SL
JournalMembr Biochem
PubMed ID2641949
'In this paper, we describe a simple and reproducible method for purifying large quantities of ryanodine receptor from skeletal muscle membranes. The procedure involves the use of ion exchange chromatography and sucrose gradient centrifugation to purify the protein which has been identified as the calcium release protein of the sarcoplasmic ... More
Modulation of ryanodine-induced Ca2+ release in amphibian skeletal muscle.
AuthorsHwang KS, Saida K, van Breemen C
JournalBiochem Biophys Res Commun
PubMed ID3103614
'We examined effects of ryanodine on tension in intact and skinned amphibian skeletal muscle. 100 microM ryanodine (RY) alone in the frog Ringer''s solution (FR) produced tension in the intact muscle reaching its peak by 1 h; 10 min treatment with RY augmented depolarization-induced tension and prevented a subsequent caffeine-induced ... More
Phase-dependent contributions from Ca2+ entry and Ca2+ release to caffeine-induced [Ca2+]i oscillations in bullfrog sympathetic neurons.
AuthorsFriel DD, Tsien RW
JournalNeuron
PubMed ID1610566
'Sympathetic neurons display robust [Ca2+]i oscillations in response to caffeine and mild depolarization. Oscillations occur at constant membrane potential, ruling out voltage-dependent changes in plasma membrane conductance. They are terminated by ryanodine, implicating Ca(2+)-induced Ca2+ release. Ca2+ entry is necessary for sustained oscillatory activity, but its importance varies within the ... More
Cyclic ADP-ribose and inositol 1,4,5-triphosphate mobilizes Ca2+ from distinct intracellular pools in permeabilized lacrimal acinar cells.
AuthorsGromada J, Jørgensen TD, Dissing S
JournalFEBS Lett
PubMed ID7883052
'In permeabilized lacrimal acinar cells, cyclic ADP-ribose (cADP-ribose) and inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) release Ca2+ in a dose dependent manner from distinct thapsigargin-sensitive Ca2+ pools. Ryanodine specifically blocks the Ca2+ response to cADP-ribose, whereas heparin strongly reduces the response to Ins(1,4,5)P3 application. GTP causes a rapid Ca2+ release by a ryanodine- ... More
Calcium mobilization evoked by hepatocellular swelling is linked to activation of phospholipase Cgamma.
AuthorsMoore AL, Roe MW, Melnick RF, Lidofsky SD
JournalJ Biol Chem
PubMed ID12167665
'Recovery from swelling of hepatocytes and selected other epithelia is triggered by intracellular Ca(2+) release from the endoplasmic reticulum, which leads to fluid and electrolyte efflux through volume-sensitive K(+) and Cl(-) channels. The aim of this study was to determine the mechanisms responsible for swelling-mediated hepatocellular Ca(2+) mobilization. Swelling of ... More
Ryanodine and inositol trisphosphate receptors are differentially distributed and expressed in rat parotid gland.
AuthorsZhang X, Wen J, Bidasee KR, Besch HR, Wojcikiewicz RJ, Lee B, Rubin RP
JournalBiochem J
PubMed ID10333498
'The present study examines the cellular distribution of the ryanodine receptor/channel (RyR) and inositol 1,4,5-trisphosphate receptor (InsP3R) subtypes in parotid acini. Using fluorescently labelled 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene-3-propionic acid glycyl-ryanodine (BODIPYtrade mark-ryanodine) and confocal microscopy, RyRs were localized primarily to the perinuclear region (basal pole) of the acinar cell. Ryanodine, Ruthenium Red, cAMP ... More
Cyclic ADP-ribose binds to FK506-binding protein 12.6 to release Ca2+ from islet microsomes.
AuthorsNoguchi N, Takasawa S, Nata K, Tohgo A, Kato I, Ikehata F, Yonekura H, Okamoto H
JournalJ Biol Chem
PubMed ID9013543
'Cyclic ADP-ribose (cADPR) is a second messenger for Ca2+ mobilization via the ryanodine receptor (RyR) from islet microsomes for insulin secretion (Takasawa, S., Nata, K., Yonekura, H., and Okamoto, H. (1993) Science 259, 370-373). In the present study, FK506, an immunosuppressant that prolongs allograft survival, as well as cADPR were ... More
Both alpha 1A- and alpha 2A-adrenoreceptor subtypes stimulate voltage-operated L-type calcium channels in rat portal vein myocytes. Evidence for two distinct transduction pathways.
AuthorsLeprêtre N, Mironneau J, Morel JL
JournalJ Biol Chem
PubMed ID7961939
'Previously, we have shown that myocytes from rat portal vein express alpha 1A-adrenoreceptors that couple with a Gq/G11-protein to stimulate phosphoinositide turnover and release of calcium from intracellular stores. The purpose of this study was to investigate the contribution of both alpha 1- and alpha 2-adrenoreceptor subtypes in inducing stimulation ... More
Glutathione modulates ryanodine receptor from skeletal muscle sarcoplasmic reticulum. Evidence for redox regulation of the Ca2+ release mechanism.
AuthorsZable AC, Favero TG, Abramson JJ
JournalJ Biol Chem
PubMed ID9054399
'In this report, we demonstrate the ability of the cellular thiol glutathione to modulate the ryanodine receptor from skeletal muscle sarcoplasmic reticulum. Reduced glutathione (GSH) inhibited Ca2+-stimulated [3H]ryanodine binding to the sarcoplasmic reticulum and inhibited the single-channel gating activity of the reconstituted Ca2+ release channel. The effects of GSH on ... More
Calmodulin interaction with the skeletal muscle sarcoplasmic reticulum calcium channel protein.
AuthorsYang HC, Reedy MM, Burke CL, Strasburg GM
JournalBiochemistry
PubMed ID8286381
'Studies were initiated to define the equilibria of calmodulin binding to the skeletal muscle sarcoplasmic reticulum (SR) Ca(2+)-release channel protein in native SR vesicles. Calmodulin affinity-labeling experiments indicated that the major calmodulin receptor in heavy SR preparations was a protein of M(r) > 450,000, corresponding to the Ca(2+)-release channel protein. ... More
Retrograde activation of store-operated calcium channel.
AuthorsMa J, Pan Z
JournalCell Calcium
PubMed ID12765683
'Store-operated Ca2+ entry represents an important mechanism for refilling of a depleted intracellular-reticulum Ca2+ store following sustained activation of the IP3 receptor or ryanodine receptor RyR/Ca2+ release channel in the endoplasmic/sarcoplasmic reticulum (ER/SR). Recent studies have demonstrated the existence of store-operated Ca2+ channel (SOC) in muscle cells, whose activation process ... More
Receptor-activated Ca2+ influx. Two independently regulated mechanisms of influx stimulation coexist in neurosecretory PC12 cells.
'Receptor-activated Ca2+ influx was investigated in PC12 cells clones loaded with fura-2. Cells were stimulated in a Ca(2+)-free medium and studied after reintroduction of the cation or addition of Mn2+ into the medium. A first influx component, independent of receptor activation and sustained by depletion of the intracellular inositol 1,4,5-trisphosphate ... More
The sarcolemmal mechanisms involved in the control of diastolic intracellular calcium in isolated rat cardiac trabeculae.
AuthorsLamont C, Eisner DA
JournalPflugers Arch
PubMed ID8781189
'We performed experiments using the calcium indicator Indo-1 to determine the relative roles of the sarcolemmal mechanisms involved in the regulation of diastolic intracellular calcium concentration ([Ca2+]i) in trabeculae from the rat heart. Ryanodine was used to eliminate sarcoplasmic reticulum (SR) function. In the functional absence of the SR, 76.8 ... More
Rapid mobilization of intracellular Mg2+ by bombesin in Swiss 3T3 cells: mobilization through external Ca(2+)- and tyrosine kinase-dependent mechanisms.
AuthorsIshijima S, Tatibana M
JournalJ Biochem (Tokyo)
PubMed ID8089090
'We examined the effects of growth factors on intracellular free Mg2+ concentrations ([Mg2+]i) in single Swiss 3T3 fibroblasts, using microfluorometry of a Mg(2+)-sensitive dye mag-fura-2. We had already noted an increase in [Mg2+]i after exposure to bombesin for 30-60 min [Ishijima, S., Sonoda, T., & Tatibana, M. (1991) Am. J. ... More
Localized Ca2+ uncaging reveals polarized distribution of Ca2+-sensitive Ca2+ release sites: mechanism of unidirectional Ca2+ waves.
AuthorsAshby MC, Craske M, Park MK, Gerasimenko OV, Burgoyne RD, Petersen OH, Tepikin AV
JournalJ Cell Biol
PubMed ID12119355
'Ca2+-induced Ca2+ release (CICR) plays an important role in the generation of cytosolic Ca2+ signals in many cell types. However, it is inherently difficult to distinguish experimentally between the contributions of messenger-induced Ca2+ release and CICR. We have directly tested the CICR sensitivity of different regions of intact pancreatic acinar ... More
Modulation by monovalent anions of calcium and caffeine induced calcium release from heavy sarcoplasmic reticulum vesicles.
AuthorsHasselbach W, Migala A
JournalZ Naturforsch [C]
PubMed ID1418241
'Both calcium and caffeine induced calcium release from actively loaded heavy sarcoplasmic reticulum vesicles were studied to analyze the dependence of both activities on the composition of the release medium with respect to monovalent anions. Calcium is unable to induce net calcium release while caffeine remains effective as releasing agent ... More
Expression and function of ryanodine receptors in nonexcitable cells.
'We have used reverse transcriptase-polymerase chain reaction to investigate the expression of ryanodine receptors in several excitable and nonexcitable cell types. Consistent with previous reports, we detected ryanodine receptor expression in brain, heart, and skeletal muscle. In addition, we detected ryanodine receptor expression in various other excitable cells including PC ... More
Cyclic ADP-ribose enhances coupling between voltage-gated Ca2+ entry and intracellular Ca2+ release.
AuthorsEmpson RM, Galione A
JournalJ Biol Chem
PubMed ID9261092
'Ca2+ release from intracellular stores can be activated in neurons by influx of Ca2+ through voltage-gated Ca2+ channels. This process, called Ca2+-induced Ca2+ release, relies on the properties of the ryanodine receptor and represents a mechanism by which Ca2+ influx during neuronal activity can be amplified into large intracellular Ca2+ ... More
Origin sites of calcium release and calcium oscillations in frog sympathetic neurons.
AuthorsMcDonough SI, Cseresnyés Z, Schneider MF
JournalJ Neurosci
PubMed ID11124983
'In many neurons, Ca(2+) signaling depends on efflux of Ca(2+) from intracellular stores into the cytoplasm via caffeine-sensitive ryanodine receptors (RyRs) of the endoplasmic reticulum. We have used high-speed confocal microscopy to image depolarization- and caffeine-evoked increases in cytoplasmic Ca(2+) levels in individual cultured frog sympathetic neurons. Although caffeine-evoked Ca(2+) ... More
The type 2 ryanodine receptor of neurosecretory PC12 cells is activated by cyclic ADP-ribose. Role of the nitric oxide/cGMP pathway.
AuthorsClementi E, Riccio M, Sciorati C, Nisticò G, Meldolesi J
JournalJ Biol Chem
PubMed ID8663443
'Of two neurosecretory PC12 cell clones that respond to NO donors and 8-bromo-cGMP with similar increases in cADP-ribose and that possess molecularly similar Ca2+ stores, only one (clone 16A) expresses the type 2 ryanodine receptor, whereas the other (clone 27) is devoid of ryanodine receptors. In PC12-16A cells, activation of ... More
Ryanodine-affinity chromatography purifies 106 kD Ca2+ release channels from skeletal and cardiac sarcoplasmic reticulum.
AuthorsSalama G, Nigam M, Shome K, Finkel MS, Lagenaur C, Zaidi NF
JournalCell Calcium
PubMed ID1337500
'A 106 kD protein was isolated from skeletal sarcoplasmic reticulum (SR) vesicles and shown to have the properties of SR Ca2+ release channels, including blockade by 5 nM ryanodine. In view of extensive reports that the ryanodine-receptor complex consists of four 565 kD junctional feet proteins (JFPs) and is the ... More
Relaxation of arterial smooth muscle by calcium sparks.
'Local increases in intracellular calcium ion concentration ([Ca2+]i) resulting from activation of the ryanodine-sensitive calcium-release channel in the sarcoplasmic reticulum (SR) of smooth muscle cause arterial dilation. Ryanodine-sensitive, spontaneous local increases in [Ca2+]i (Ca2+ sparks) from the SR were observed just under the surface membrane of single smooth muscle cells ... More
The ryanodine receptor/Ca2+ release channel.
AuthorsMcPherson PS, Campbell KP
JournalJ Biol Chem
PubMed ID8390976
Phenylephrine induces endothelium-independent rhythmic contraction in rabbit mesenteric arteries treated with ryanodine.
AuthorsOmote M, Kajimoto N, Mizusawa H
JournalActa Physiol Scand
PubMed ID1519486
Ryanodine receptor channel of sarcoplasmic reticulum.
AuthorsFill M, Coronado R
JournalTrends Neurosci
PubMed ID2469164
Ca2+ and activation mechanisms in skeletal muscle.
AuthorsAshley CC, Mulligan IP, Lea TJ
JournalQ Rev Biophys
PubMed ID2047521
The use of ryanodine and calcium channel blockers to characterize intra- and extracellular calcium pools mobilized by noradrenaline in the rat vas deferens.
AuthorsVesperinas G, Feddersen M, Lewin J, Huidobro-Toro JP
JournalEur J Pharmacol
PubMed ID2776834
Ryanodine (0.03-10 microM) abolished the phasic component of the contractile response to noradrenaline in the rat vas deferens but had less effect on the tonic component of this response. In contrast, nifedipine and methoxyverapamil (D600, 0.3-0.8 microM) blocked only the tonic component of the noradrenaline, adrenaline or phenylephrine-induced contractions. These ... More
Ca(2+)-induced Ca2+ release in insulin-secreting cells.
AuthorsIslam MS, Rorsman P, Berggren PO
JournalFEBS Lett
PubMed ID1537406
The sulphydryl reagent thimerosal (50 microM) released Ca2+ from a non-mitochondrial intracellular Ca2+ pool in a dose-dependent manner in permeabilized insulin-secreting RINm5F cells. This release was reversed after addition of the reducing agent dithiothreitol. Ca2+ was released from an Ins(1,4,5)P3-insensitive pool, since release was observed even after depletion of the ... More
Skeletal muscle ryanodine receptor is a redox sensor with a well defined redox potential that is sensitive to channel modulators.
AuthorsXia R, Stangler T, Abramson JJ
JournalJ Biol Chem
PubMed ID10952995
Hyperreactive sulfhydryl groups associated with the Ca(2+) release protein from sarcoplasmic reticulum are shown to have a well defined reduction potential that is sensitive to the cellular environment. Ca(2+) channel activators lower the redox potential of the ryanodine receptor, which favors the oxidation of thiols and the opening of the ... More
Effects of ryanodine on cardiac subcellular membrane fractions.
AuthorsBesch HR
JournalFed Proc
PubMed ID2415404
Both the rate and the steady-state magnitude of net calcium accumulation by cardiac sarcoplasmic reticulum (SR) vesicles are increased by ryanodine. Sarcolemmal calcium transport mechanisms are not affected. The apparent augmentation of calcium accumulation by membrane vesicles from junctional SR derives not from an increase in the rate at which ... More
Quantal Ca2+ mobilization by ryanodine receptors is due to all-or-none release from functionally discrete intracellular stores.
AuthorsCheek TR, Berridge MJ, Moreton RB, Stauderman KA, Murawsky MM, Bootman MD
JournalBiochem J
PubMed ID8053911
Low caffeine concentrations were unable to completely release the caffeine- and ryanodine-sensitive intracellular Ca2+ pool in intact adrenal chromaffin cells. This 'quantal' Ca2+ release is the same as that previously observed with inositol Ins(1,4,5)P3-induced Ca2+ release. The molecular mechanism underlying quantal Ca2+ release from the ryanodine receptor was investigated using ... More
Ryanodine: a modifier of sarcoplasmic reticulum calcium release in striated muscle.
AuthorsSutko JL, Ito K, Kenyon JL
JournalFed Proc
PubMed ID2415406
We have proposed that the naturally occurring alkaloid ryanodine reduces the release of calcium from the sarcoplasmic reticulum (SR) in cardiac muscle cells. We summarize the data that support this hypothesis and discuss possible mechanisms for 1) the differences in sensitivity to ryanodine displayed by intact skeletal and cardiac muscle ... More
Influence of Na/Ca exchange and mobilization of intracellular calcium on the time course of the slow afterhyperpolarization current (IAHP) in bullfrog sympathetic ganglion neurons.
IAHP is a calcium dependent potassium current that underlies slow afterhyperpolarizations following action potentials in bullfrog sympathetic ganglion neurons. The decay rate of IAHP increases with increasing calcium loads. This effect was found not to be due to mobilization on intracellular calcium from ryanodine and caffeine sensitive stores. The relation ... More
Cyclic ADP-ribose regulation of ryanodine receptors involved in agonist evoked cytosolic Ca2+ oscillations in pancreatic acinar cells.
AuthorsThorn P, Gerasimenko O, Petersen OH
JournalEMBO J
PubMed ID7514529
We have investigated the role of the ryanodine-sensitive intracellular Ca2+ release channel (ryanodine receptor) in the cytosolic Ca2+ oscillations evoked in pancreatic acinar cells by acetylcholine (ACh) or cholecystokinin (CCK). Ryanodine abolished or markedly inhibited the agonist evoked Ca2+ spiking, but enhanced the frequency of spikes evoked by direct internal ... More
Ca(2+)-induced Ca2+ release in sea urchin egg homogenates: modulation by cyclic ADP-ribose.
AuthorsGalione A, Lee HC, Busa WB
JournalScience
PubMed ID1909457
Calcium-induced calcium release (CICR) may function widely in calcium-mediated cell signaling, but has been most thoroughly characterized in muscle cells. In a homogenate of sea urchin eggs, which display transients in the intracellular free calcium concentration ([Ca2+]i) during fertilization and anaphase, addition of Ca2+ triggered CICR. Ca2+ release was also ... More
Spontaneous myocardial calcium oscillations: overview with emphasis on ryanodine and caffeine.
AuthorsLakatta EG, Capogrossi MC, Kort AA, Stern MD
JournalFed Proc
PubMed ID4065356
All mammalian cardiac preparations exhibit the capacity for periodic spontaneous Ca2+ release from the sarcoplasmic reticulum (SR) (Ca2+ oscillations). The occurrence of such oscillations in unstimulated preparations and their periodicity depend on the species and the Ca2+ load on the cell. When the spontaneous frequency of these oscillations exceeds the ... More
Axonal activation-induced calcium transients in myelinating Schwann cells, sources, and mechanisms.
AuthorsLev-Ram V, Ellisman MH
JournalJ Neurosci
PubMed ID7722618
We have investigated the role of myelinating glia in events associated with propagation of the action potential at nodes of Ranvier using combinations of optical and electrophysiological recording methods. Calcium transients were observed in Schwann cells by fluorescent imaging of the nodal complex of fibers loaded with the calcium-sensitive dye ... More
Generation of calcium oscillations in fibroblasts by positive feedback between calcium and IP3.
AuthorsHarootunian AT, Kao JP, Paranjape S, Tsien RY
JournalScience
PubMed ID1986413
A wide variety of nonexcitable cells generate repetitive transient increases in cytosolic calcium ion concentration ([Ca2+]i) when stimulated with agonists that engage the phosphoinositide signalling pathway. Current theories regarding the mechanisms of oscillation disagree on whether Ca2+ inhibits or stimulates its own release from internal stores and whether inositol 1,4,5-trisphosphate ... More
Multistep mechanism of polarized Ca2+ wave patterns in hepatocytes.
AuthorsNathanson MH, Burgstahler AD, Fallon MB
JournalAm J Physiol
PubMed ID7943230
The spatial organization of cytosolic Ca2+ (Ca2+i) signals is thought to be important for regulation of cell function. In epithelial cells, the involvement of inositol 1,4,5-trisphosphate (IP3)-mediated Ca2+ release in evoking Ca2+i signals is appreciated, but the location of IP3-sensitive Ca2+ stores and the role of Ca(2+)-induced Ca2+ release (CICR) ... More
Intracellular calcium pools in neuroblastoma x glioma hybrid NG108-15 cells.
AuthorsChueh SH, Liu JA, Kao LS
JournalJ Neurochem
PubMed ID2144581
The intracellular nonmitochondrial calcium pools of saponin-permeabilized NG108-15 cells were characterized using inositol 1,4,5-trisphosphate (IP3) and GTP. IP3 or GTP alone induced release of 47 and 68%, respectively, of the calcium that was releasable by A23187. GTP induced release of a further 24% of the calcium after IP3 treatment, whereas ... More
Free cytoplasmic Ca2+ concentration oscillations in thapsigargin-treated parotid acinar cells are caffeine- and ryanodine-sensitive.
AuthorsFoskett JK, Wong D
JournalJ Biol Chem
PubMed ID1830587
The microsomal Ca-ATPase inhibitor thapsigargin induces in rat salivary acinar cells [Ca2+]i oscillations which, though similar to those activated by agonists, are independent of inositol phosphates or inositol 1,4,5-trisphosphate (IP3)-sensitive intracellular Ca2+ stores (Foskett, J. K., Roifman, C., and Wong, D. (1991) J. Biol. Chem. 266, 2778-2782). To examine whether ... More
ATP-dependent accumulation and inositol trisphosphate- or cyclic ADP-ribose-mediated release of Ca2+ from the nuclear envelope.
Uptake and release of Ca2+ from isolated liver nuclei were studied with fluorescent probes. We show with the help of digital imaging and confocal microscopy that the Ca(2+)-sensitive fluorescent probe Fura 2 is concentrated in or around the nuclear envelope and that the distribution of Fura 2 fluorescence is similar ... More
Differential involvement of phospholipase A2/arachidonic acid and phospholipase C/phosphoinositol pathways during cholecystokinin receptor activated Ca2+ oscillations in pancreatic acini.
AuthorsTsunoda Y, Owyang C
JournalBiochem Biophys Res Commun
PubMed ID7688962
In pancreatic acini, administration of the phospholipase C inhibitor, U-73122, abolished Ca2+ oscillations and amylase secretion induced by CCK but had much less effect on the action of CCK analog JMV-180. In contrast, the phospholipase A2 inhibitor, ONO-RS-082, inhibited both Ca2+ spikes and amylase secretion induced by JMV-180, but it ... More
Intraluminal Ca2+ dependence of Ca2+ and ryanodine-mediated regulation of skeletal muscle sarcoplasmic reticulum Ca2+ release.
AuthorsGilchrist JS, Belcastro AN, Katz S
JournalJ Biol Chem
PubMed ID1400399
The action of ryanodine upon sarcoplasmic reticulum (SR) Ca2+ handling is controversial with evidence for both activation and inhibition of SR Ca2+ release. In this study, the role of the intraluminal SR Ca2+ load was probed as a potential regulator of ryanodine-mediated effects upon SR Ca2+ release. Through dual-wavelength spectroscopy ... More
Calexcitin interaction with neuronal ryanodine receptors.
Calexcitin (CE), a Ca2+- and GTP-binding protein, which is phosphorylated during memory consolidation, is shown here to co-purify with ryanodine receptors (RyRs) and bind to RyRs in a calcium-dependent manner. Nanomolar concentrations of CE released up to 46% of the 45Ca label from microsomes preloaded with 45CaCl2. This release was ... More
Muscarinic and nicotinic ACh receptor activation differentially mobilize Ca2+ in rat intracardiac ganglion neurons.
AuthorsBeker F, Weber M, Fink RH, Adams DJ
JournalJ Neurophysiol
PubMed ID12761283
The origin of intracellular Ca2+ concentration ([Ca2+]i) transients stimulated by nicotinic (nAChR) and muscarinic (mAChR) receptor activation was investigated in fura-2-loaded neonatal rat intracardiac neurons. ACh evoked [Ca2+]i increases that were reduced to approximately 60% of control in the presence of either atropine (1 microM) or mecamylamine (3 microM) and ... More
Amplification of nitric oxide signaling by interstitial cells isolated from canine colon.
AuthorsPublicover NG, Hammond EM, Sanders KM
JournalProc Natl Acad Sci U S A
PubMed ID8446634
The effects of nitric oxide (NO) on intracellular Ca2+ concentration ([Ca2+]i) were studied in enzymatically dispersed interstitial cells (ICs) and smooth muscle cells (SMCs) isolated from canine colon. [Ca2+]i was monitored by using fluo-3 and video fluorescence imaging techniques. Exogenous NO caused an increase in [Ca2+]i in ICs and a ... More
Homogeneous Ca2+ stores in rat adrenal chromaffin cells.
AuthorsInoue M, Sakamoto Y, Fujishiro N, Imanaga I, Ozaki S, Prestwich GD, Warashina A
JournalCell Calcium
PubMed ID12526884
The localization and function of Ca(2+) stores in isolated chromaffin cells of rat adrenal medulla were investigated using confocal laser microscopy and amperometry. Binding sites for BODIPY-inositol 1,4,5-trisphosphate (IP(3)), -ryanodine (Ry), and -thapsigargin (Thap) were both perinuclear and at the cell periphery. The endoplasmic reticulum (ER), which was identified by ... More
Possible regulation of caffeine-induced intracellular Ca2+ mobilization by intracellular free Na+.
AuthorsSorimachi M, Yamagami K, Nishimura S, Kuramoto K
JournalJ Neurochem
PubMed ID1431907
To gain some understanding of the regulatory mechanism involved in caffeine-induced Ca2+ release in adrenal chromaffin cells, we took advantage of the paradoxical observation that removal of divalent cations potentiated the secretory response to caffeine. We measured the concentration of cytosolic free Ca2+ ([Ca]in) in isolated cat chromaffin cells, by ... More
Amino- and guanidinoacylryanodines: basic ryanodine esters with enhanced affinity for the sarcoplasmic reticulum Ca(2+)-release channel.
Amino- and guanidinoacyl esters of ryanodine were prepared to evaluate the effect of basicity on the binding affinity of these derivatives for the sarcoplasmic reticulum Ca(2+)-release channel (SR CRC). In the presence of DCC and DMAP Cbz-beta-alanine reacts with ryanodine in CH2Cl2 to give O10eq-Cbz-beta-alanylryanodine (3a), which on hydrogenolysis yields ... More
Putative receptor for inositol 1,4,5-trisphosphate similar to ryanodine receptor.
AuthorsMignery GA, Südhof TC, Takei K, De Camilli P
JournalNature
PubMed ID2554146
Inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) serves as an intracellular second messenger for several neurotransmitters, hormones and growth factors by initiating calcium release from intracellular stores. A cerebellar Ins(1,4,5)P3 receptor has been characterized biochemically and shown by immunocytochemistry to be present in intracellular membranes in Purkinje cells. We show that a previously described ... More
Noradrenaline-activated heparin-sensitive Ca2+ entry after depletion of intracellular Ca2+ store in portal vein smooth muscle cells.
Single portal vein smooth muscle cells were voltage-clamped using the whole cell patch-clamp technique. Intracellular free Ca2+ concentration ([Ca2+]i) was simultaneously monitored using the fluorescence from the dye indo-1. Noradrenaline (NA, 10 microM) evoked a transient increase in [Ca2+]i, due to inositol 1,4,5-trisphosphate (InP3)-induced Ca2+ release, followed by a sustained ... More
Trypsin destruction of the high affinity ryanodine binding sites of the junctional sarcoplasmic reticulum.
AuthorsShoshan-Barmatz V, Zarka A
JournalJ Biol Chem
PubMed ID3182812
Tryptic digestion of the junctional sarcoplasmic reticulum membranes in sucrose but not NaCl buffer leads to complete loss of ryanodine binding capacity. The presence of MgCl2 in the sucrose buffer prevents the loss of ryanodine binding by the trypsin treatment. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the treated membranes reveal ... More
Effects of LP-805, a new vasodilating agent, on cytosolic Ca2+ and contraction in vascular smooth muscle of rat aorta.
AuthorsKishii K, Inazu M, Morimoto T, Tsujitani M, Takayanagi I
JournalGen Pharmacol
PubMed ID1511847
1. LP-805 (0.1-10 microM) caused the reduction in norepinephrine (NE)-and serotonin (5-HT)-induced maximum response, a parallel shift of the concentration-response curve for prostaglandin F2 alpha (PGF2 alpha), in a concentration-dependent manner, but not K(+)-induced maximum response. 2. In Ca(2+)-free solution, LP-805 (0.1-10 microM) markedly inhibited the phasic contraction induced by ... More
Characterization of recombinant rabbit cardiac and skeletal muscle Ca2+ release channels (ryanodine receptors) with a novel [3H]ryanodine binding assay.
AuthorsDu GG, Imredy JP, MacLennan DH
JournalJ Biol Chem
PubMed ID9837897
A rapid assay for high affinity [3H]ryanodine binding to 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonic acid (CHAPS)-solubilized recombinant or native Ca2+ release channel proteins (ryanodine receptor, RyR) was devised. The key to preservation of high affinity [3H]ryanodine binding sites in the presence of increasing concentrations of CHAPS was the addition of phosphatidylcholine. This assay was ... More
Inositol 1,4,5-trisphosphate directs Ca(2+) flow between mitochondria and the Endoplasmic/Sarcoplasmic reticulum: a role in regulating cardiac autonomic Ca(2+) spiking.
AuthorsJaconi M, Bony C, Richards SM, Terzic A, Arnaudeau S, Vassort G, Pucéat M
JournalMol Biol Cell
PubMed ID10793156
The signaling role of the Ca(2+) releaser inositol 1,4, 5-trisphosphate (IP(3)) has been associated with diverse cell functions. Yet, the physiological significance of IP(3) in tissues that feature a ryanodine-sensitive sarcoplasmic reticulum has remained elusive. IP(3) generated by photolysis of caged IP(3) or by purinergic activation of phospholipase Cgamma slowed ... More