Muscarinic receptor-mediated calcium efflux from cultured bovine adrenal chromaffin cells.
The effect of stimulation of the muscarinic receptor on Ca2+ mobilization in cultured bovine adrenal chromaffin cells was examined. Acetylcholine (ACh) increased the uptake of 45Ca2+ and [Ca2+]i whose levels decreased with time after reaching peaks. It also enhanced the efflux of 45Ca2+ from the cells. Its effect was inhibited by the specific muscarinic receptor antagonist atropine (Atr), but not by the nicotinic receptor antagonist hexamethonium (C6). The increase in muscarine (Mus)-stimulated 45Ca2+ efflux was reduced concentration-dependently by deprivation of extracellular Na+. These results suggest that muscarinic stimulation of the ACh receptor stimulates Na+/Ca2+ exchange in cultured bovine adrenal chromaffin cells.
Houchi
H
H
Department of Pharmacology, Tokushima University School of Medicine, Japan.
Masuda
Y
Y
Murakumo
Y
Y
Ishimura
Y
Y
Ohuchi
T
T
Oka
M
M
D000109:Acetylcholine / Q000494:pharmacology; D000313:Adrenal Medulla / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D002118:Calcium / Q000378:metabolism*; D002417:Cattle; D002478:Cells, Cultured; D002837:Chromaffin Granules / Q000187:drug effects / Q000378:metabolism*; D009116:Muscarine / Q000494:pharmacology; D009538:Nicotine / Q000494:pharmacology; D011976:Receptors, Muscarinic / Q000502:physiology*
D011976:Receptors, Muscarinic; D009538:Nicotine; D009116:Muscarine; D000109:Acetylcholine; D002118:Calcium