Role of Ca2+ in response of adrenal glomerulosa cells to angiotensin II, ACTH, K+, and ouabain.
The effects of Na+-K+-ATPase inhibition by ouabain and blockage of Ca2+ influx into the cell by verapamil and lanthanum on the response of isolated rat adrenal glomerulosa cells to angiotensin II, ACTH, and K+ were studied. Ouabain significantly increased basal aldosterone output at a concentration of 10(-5) mol/liter, whereas at 10(-3) mol/liter basal secretion was unaffected. Steroidogenic response to angiotensin II was significantly potentiated at concentrations of ouabain of 10(-5) mol/liter, but responses to angiotensin II, ACTH, and K+ were inhibited by 10(-4) and 10(-3) mol/liter of ouabain. The Ca2+ antagonist verapamil (10(-6) to 10(-4) mol/liter) decreased basal aldosterone secretion as well as the response to angiotensin II, ACTH, and K+. The effects of ouabain (10(-5) mol/liter) on basal and stimulated steroidogenesis were abolished by verapamil (10(-4) mol/liter). Lanthanum decreased basal and angiotensin II, ACTH, and K+ induced aldosterone secretion. The effects of ouabain (10(-5) mol/liter) on basal and stimulated aldosterone biosynthesis were blocked by lanthanum. These results suggest that Ca2+ mediates the effects of angiotensin II, ACTH, K+ and Na+-K+-ATPase inhibition on aldosterone biosynthesis. Ca2+ may be the final common intracellular messenger of most aldosterone secretagogues.
D000311:Adrenal Glands / Q000187:drug effects / Q000502:physiology*; D000324:Adrenocorticotropic Hormone / Q000494:pharmacology*; D000450:Aldosterone / Q000378:metabolism*; D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D007700:Kinetics; D007811:Lanthanum / Q000494:pharmacology; D010042:Ouabain / Q000494:pharmacology*; D011188:Potassium / Q000494:pharmacology*; D051381:Rats; D014700:Verapamil / Q000494:pharmacology
D000804:Angiotensin II; D000450:Aldosterone; D010042:Ouabain; D007811:Lanthanum; D000324:Adrenocorticotropic Hormone; D014700:Verapamil; D011188:Potassium; D002118:Calcium