Calcium is essential for ATP-induced steroidogenesis in bovine adrenocortical fasciculata cells.
The effect of extracellular ATP on steroidogenesis in primary cultured bovine adrenocortical fasciculata cells was investigated. I observed that in the presence of extracellular Ca2+, ATP caused a dose-dependent elevation of intracellular Ca2+ ([Ca2+]i) and induced steroidogenesis concentration- and time-dependently. However, in the absence of extracellular Ca2+, ATP had no effect on steroidogenesis. In the presence of extracellular Ca2+, calmodulin inhibitors inhibited the ATP-induced steroidogenesis, but dihydropyridine calcium channel blockers did not. Furthermore, ATP did not cause an elevation of cyclic AMP in bovine adrenocortical fasciculata cells even if extracellular Ca2+ existed. These results suggest that extracellular ATP might have an influence on bovine adrenocortical cells via the purinoceptor (P2Y) in connection with calcium mobilization, open the non-selective calcium channel and induce steroidogenesis by means of an elevation of [Ca2+]i via the calcium-calmodulin system.
Niitsu
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Department of Internal Medicine (III), Jikei University School of Medicine, Tokyo, Japan.
D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000494:pharmacology / Q000502:physiology*; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002147:Calmodulin / Q000037:antagonists & inhibitors; D002417:Cattle; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism; D007457:Iodine Radioisotopes; D013256:Steroids / Q000096:biosynthesis*; D015383:Zona Fasciculata / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*
D002121:Calcium Channel Blockers; D002147:Calmodulin; D007457:Iodine Radioisotopes; D013256:Steroids; D000255:Adenosine Triphosphate; D000242:Cyclic AMP; D002118:Calcium