Loading...
Please wait, while we are loading the content...
Similar Documents
Ryanodine Inhibits Caffeine-Evoked $Ca^{2+}$Mobilization and Catecholamine Secretion from Cultured Bovine Adrenal Chromaffin Cells
| Content Provider | Scilit |
|---|---|
| Author | Teraoka, Hiroki Nakazato, Yoshikazu Ohga, Akira |
| Copyright Year | 1991 |
| Description | Journal: Journal of Neurochemistry The effects of ryanodine, a selective inhibitor of the Ca(2+)-induced Ca2+ release mechanism, on caffeine-evoked changes in cytosolic Ca2+ concentration ([Ca2+]i) and catecholamine secretion were investigated using cultured bovine adrenal chromaffin cells. Caffeine (5-40 mM) caused a concentration-dependent transient rise in [Ca2+]i and catecholamine secretion in Ca2+/Mg(2+)-free medium containing 0.2 mM EGTA. Ryanodine (5 x 10(-5) M) alone had no effect on either [Ca2+]i or catecholamine secretion. Although the application of ryanodine plus caffeine caused the same increase in both [Ca2+]i and catecholamine secretion as those induced by caffeine alone, ryanodine (4 x 10(-7) - 5 x 10(-5) M) irreversibly prevented the increase in both [Ca2+]i and catecholamine secretion resulting from subsequent caffeine application over a range of concentrations. The secretory response to caffeine was markedly enhanced by replacement of Na+ with sucrose in Ca2+/Mg(2+)-free medium, and this enhanced response was also blocked by ryanodine. Caffeine was found to decrease the susceptibility of the secretory apparatus to Ca2+ in digitonin-permeabilized cells. These results indicate that caffeine mobilizes Ca2+ from intracellular stores, the function of which is irreversibly blocked by ryanodine, resulting in the increase in catecholamine secretion in the bovine adrenal chromaffin cell. |
| Ending Page | 1890 |
| Starting Page | 1884 |
| ISSN | 2573508X |
| e-ISSN | 14714159 |
| DOI | 10.1111/j.1471-4159.1991.tb06399.x |
| Journal | Journal of Neurochemistry |
| Issue Number | 6 |
| Volume Number | 57 |
| Language | English |
| Publisher | Wiley-Blackwell |
| Publisher Date | 1991-12-01 |
| Access Restriction | Open |
| Subject Keyword | Journal: Journal of Neurochemistry Endocrinology and Metabolism Adrenal Chromaffin Cells—caffeine—calcium Store—cytosolic Free Ca2+ Level—catecholamine Secretion—ryanodine Teraoka H. Et Al. Ryanodine Inhibits Caffeine‐evoked Ca2+ Mobilization and Catecholamine Secretion From Cultured Bovine Adrenal Chromaffin Cells |
| Content Type | Text |
| Resource Type | Article |
