Relationships between calcium and pH in the regulation of the slow afterhyperpolarization in cultured rat hippocampal neurons.
AuthorsKelly T, Church J
JournalJ Neurophysiol
PubMed ID16885515
'The Ca(2+)-dependent slow afterhyperpolarization (AHP) is an important determinant of neuronal excitability. Although it is established that modest changes in extracellular pH (pH(o)) modulate the slow AHP, the relative contributions of changes in the priming Ca(2+) signal and intracellular pH (pH(i)) to this effect remain poorly defined. To gain a ... More
Potential contribution of a voltage-activated proton conductance to acid extrusion from rat hippocampal neurons.
AuthorsCheng YM, Kelly T, Church J,
JournalNeuroscience
PubMed ID18201832
'We examined the potential contribution of a voltage-gated proton conductance (gH+) to acid extrusion from cultured postnatal rat hippocampal neurons. In neurons loaded with Ca2+- and/or pH-sensitive fluorophores, transient exposures to 25-139.5 mM external K+ (K+o) or 20 microM veratridine in the presence of 2 mM Ca2+o (extracellular pH (pHo) ... More
Fluorescent indicators for intracellular pH.
AuthorsHan J, Burgess K,
JournalChem Rev
PubMed ID19831417
This review is about intracellular pH sensors, includingsmall fluorescent organic molecules, nanoparticles, andfluorescent proteins, e.g., GFP. It focuses on their preparations, photophysical properties, and advantages/disadvantagesfor intracellular pH measurements. The discussion is limitedto fluorescent indicators that have been applied to measureintracellular pH values since 1980. ... More
Synthesis and photophysical properties of new fluorinated benzo[c]xanthene dyes as intracellular pH indicators.
AuthorsLiu J, Diwu Z, Leung WY
JournalBioorg Med Chem Lett
PubMed ID11677123
Two new fluorinated benzo[c]xanthene dyes were synthesized by reaction of fluorinated 1,6-dihydroxynaphthalenes with 2,4- (and 2,5)-dicarboxy-3'-dimethylamino-2'-hydroxybenzophenone. The two critical fluorinated 1,6-dihydroxynaphthalene intermediates were prepared via a regioselective route. The fluorinated benzo[c]xanthene dyes exhibit desired lower pK(a) values (6.4 and 7.2, respectively) than their parent compound (pK(a)=7.5) while the pH-dependent dual-emission ... More
Time-domain fluorescence lifetime imaging for intracellular pH sensing in living tissues.
AuthorsHille C, Berg M, Bressel L, Munzke D, Primus P, Löhmannsröben HG, Dosche C,
JournalAnal Bioanal Chem
PubMed ID18481048
pH sensing in living cells represents one of the most prominent topics in biochemistry and physiology. In this study we performed one-photon and two-photon time-domain fluorescence lifetime imaging with a laser-scanning microscope using the time-correlated single-photon counting technique for imaging intracellular pH levels. The suitability of different commercial fluorescence dyes ... More
Concurrent measurements of the free cytosolic concentrations of H+ and Na+ ions with fluorescent indicators.
AuthorsSheldon C, Cheng YM, Church J,
JournalPflugers Arch
PubMed ID15452716
We report a method for the concurrent measurement of intracellular [Na+] ([Na+ ]i) and pH (pHi) in cells co-loaded with SBFI, a Na+-sensitive fluorophore, and either carboxy SNARF-1 or SNARF-5F, H+-sensitive fluorophores. With the optical filters specified, fluorescence emissions from SBFI and either SNARF derivative were sufficiently distinct to allow ... More
HCO3(-) secretion by murine nasal submucosal gland serous acinar cells during Ca2+-stimulated fluid secretion.
AuthorsLee RJ, Harlow JM, Limberis MP, Wilson JM, Foskett JK,
JournalJ Gen Physiol
PubMed ID18591422
Airway submucosal glands contribute to airway surface liquid (ASL) composition and volume, both important for lung mucociliary clearance. Serous acini generate most of the fluid secreted by glands, but the molecular mechanisms remain poorly characterized. We previously described cholinergic-regulated fluid secretion driven by Ca(2+)-activated Cl(-) secretion in primary murine serous ... More
The chloride transporter Na(+)-K(+)-Cl- cotransporter isoform-1 contributes to intracellular chloride increases after in vitro ischemia.
Ischemic episodes in the CNS cause significant disturbances in neuronal ionic homeostasis. To directly measure changes in intracellular Cl- concentration ([Cl-]i) during and after ischemia, we used Clomeleon, a novel ratiometric optical indicator for Cl-. Hippocampal slices from adult transgenic mice expressing Clomeleon in hippocampal neurons were subjected to 8 ... More
NHE2 is the main apical NHE in mouse colonic crypts but an alternative Na+-dependent acid extrusion mechanism is upregulated in NHE2-null mice.
The mechanism of apical Na(+)-dependent H(+) extrusion in colonic crypts is controversial. With the use of confocal microscopy of the living mouse distal colon loaded with BCECF or SNARF-5F (fluorescent pH sensors), measurements of intracellular pH (pH(i)) in epithelial cells at either the crypt base or colonic surface were reported. ... More
The extracellular loop of pendrin and prestin modulates their voltage-sensing property.
Authors
JournalJ Biol Chem
PubMed ID29777056
The Oscillating Stimulus Transporter Assay, OSTA: Quantitative Functional Imaging of Transporter Protein Activity in Time and Frequency Domains.
Authors
JournalMol Cell
PubMed ID27716484
Systematic quantification of the anion transport function of pendrin (SLC26A4) and its disease-associated variants.
Authors
JournalHum Mutat
PubMed ID31599023
Live Cell Imaging Reveals pH Oscillations in Saccharomyces cerevisiae During Metabolic Transitions.