Angiotensin-induced steroidogenesis in rabbit adrenal: effects of pH and calcium.
The effect of variations in pH and Ca2+ on angiotensin II (A-II)-induced steroidogenesis was tested on isolated adrenal glomerulosa cell suspensions. The results show that a reduction in pH from 7.4 to 6.5 produces both a shift to the left of the A-II dose-response curve as well as an increase in maximum steroid production. In contrast, removal of Ca2+ from the incubation medium virtually abolished steroidogenesis to A-II (5 X 10(-9)M(, KCl(10mM) and ACTH (250 microU/ml). The Ca2+ antagonist D-600, however, was less effective than simple removal of Ca2+ as 10(-4) M was required to block the steroidogenic response to these same agonists. The results indicate that the response characteristics of this system to A-II resemble most closely those seen with isolated arterial smooth muscle - especially rabbit aortic strips.
D000302:Adrenal Cortex / Q000378:metabolism*; D000324:Adrenocorticotropic Hormone / Q000494:pharmacology; D000450:Aldosterone / Q000096:biosynthesis*; D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D006863:Hydrogen-Ion Concentration; D008297:Male; D011817:Rabbits
D000804:Angiotensin II; D000450:Aldosterone; D000324:Adrenocorticotropic Hormone; D002118:Calcium