Role of Ca2+/K+ ion exchange in intracellular storage and release of Ca2+.
AuthorsNguyen T, Chin WC, Verdugo P
JournalNature
PubMed ID9804425
'Although fluctuations in cytosolic Ca2+ concentration have a crucial role in relaying intracellular messages in the cell, the dynamics of Ca2+ storage in and release from intracellular sequestering compartments remains poorly understood. The rapid release of stored Ca2+ requires large concentration gradients that had been thought to result from low-affinity ... More
Mouse mast cell secretory granules can function as intracellular ionic oscillators.
AuthorsQuesada I, Chin WC, Steed J, Campos-Bedolla P, Verdugo P
JournalBiophys J
PubMed ID11325716
Fluorescent Ca2+ probes and digital photo-sectioning techniques were used to directly study the dynamics of Ca2+ in isolated mast cell granules of normal (CB/J) and beige (Bg(j)/Bg(j)) mice. The resting intraluminal free Ca2+ concentration ([Ca2+]L) is 25 +/- 4.2 microM (mean +/- SD, n = 68). Exposure to 3 microM ... More
Effects of calcium buffering on glucose-induced insulin release in mouse pancreatic islets: an approximation to the calcium sensor.
AuthorsPertusa JA, Sanchez-Andres JV, Martín F, Soria B
JournalJ Physiol
PubMed ID10523416
1. The properties of the calcium sensor for glucose-induced insulin secretion have been studied using cell-permeant Ca2+ buffers with distinct kinetics and affinities. In addition, submembrane cytosolic Ca2+ distribution has been modelled after trains of glucose-induced action potential-like depolarizations. 2. Slow Ca2+ buffers (around 1 mmol l-1 intracellular concentration) with ... More
ATP-independent luminal oscillations and release of Ca2+ and H+ from mast cell secretory granules: implications for signal transduction.
AuthorsQuesada I, Chin WC, Verdugo P
JournalBiophys J
PubMed ID12885643
InsP(3) is an important link in the intracellular information network. Previous observations show that activation of InsP(3)-receptor channels on the granular membrane can turn secretory granules into Ca(2+) oscillators that deliver periodic trains of Ca(2+) release to the cytosol (T. Nguyen, W. C. Chin, and P. Verdugo, 1998, Nature, 395:908-912; ... More