Functional relation between caffeine- and muscarine-sensitive Ca2+ stores and no Ca2+ releasing action of cyclic adenosine diphosphate-ribose in guinea-pig adrenal chromaffin cells

In voltage-clamped guinea-pig chromaffin cells, muscarine (50 microM) or caffeine (30 mM) produced a transient intracellular Ca(2+) concentration ([Ca(2+)](i)) increase, catecholamine release and an outward K(+) current mediated through Ca(2+) released from internal Ca(2+) stores at a holding potent...

Full description

Saved in:
Bibliographic Details
Published in:Neuroscience letters 2002-07, Vol.326 (3), p.167-170
Main Authors: OHTA, Toshio, WAKADE, Arun R, YONEKUBOA, Kazuki, ITOA, Shigeo
Format: Article
Language:English
Subjects:
Adrenal Glands - drug effects
Adrenal Glands - physiology
Adrenals. Interrenals
Adrenomedullary hormones. Regulation
Animals
Biological and medical sciences
Caffeine - pharmacology
Calcium - metabolism
Cells, Cultured
Central Nervous System Stimulants - pharmacology
Chromaffin Cells - drug effects
Chromaffin Cells - metabolism
Cyclic ADP-Ribose - administration & dosage
Cyclic ADP-Ribose - antagonists & inhibitors
Cyclic ADP-Ribose - pharmacology
Dialysis
Fundamental and applied biological sciences. Psychology
Guinea Pigs
Inositol 1,4,5-Trisphosphate - administration & dosage
Inositol 1,4,5-Trisphosphate - pharmacology
Male
Membrane Potentials - drug effects
Muscarine - pharmacology
Muscarinic Agonists - pharmacology
Patch-Clamp Techniques
Vertebrates: endocrinology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In voltage-clamped guinea-pig chromaffin cells, muscarine (50 microM) or caffeine (30 mM) produced a transient intracellular Ca(2+) concentration ([Ca(2+)](i)) increase, catecholamine release and an outward K(+) current mediated through Ca(2+) released from internal Ca(2+) stores at a holding potential of -40 mV. Caffeine followed by muscarine failed to evoke these responses, while muscarine followed by caffeine was effective in producing about 30% of [Ca(2+)](i) increase and catecholamine secretion. In cells dialyzed with inositol 1,4,5-trisphosphate (IP(3)), caffeine failed to produce the [Ca(2+)](i) increase. Intracellular application of cyclic adenosine 5'-diphosphate-ribose (cADP-ribose) or 8-bromo cADP-ribose exerted no effect on the resting [Ca(2+)](i) and the caffeine-induced [Ca(2+)](i) increase. These results suggest that IP(3)-sensitive stores are functionally divided into two subpopulations, sensitive and insensitive to caffeine, and it is unlikely that cADP-ribose plays a role as a Ca(2+) releaser in guinea-pig adrenal chromaffin cells.
ISSN:0304-3940
1872-7972
DOI:10.1016/S0304-3940(02)00333-6