Regulation of aldosterone secretion by a new aldosterone stimulating factor.
The site of action in the steroidogenic pathway of aldosterone stimulating factor (ASF), isolated from human urine, was studied in collagenase-dispersed rabbit adrenal capsular cells and compared with those of beta-lipotropin (beta-LPH), angiotensin II (A II) and adrenocorticotropic hormone (ACTH). When incubated with adrenal cell suspension at 37 degrees C for 2 hours, ASF, beta-LPH and ACTH induced dose-related increases in aldosterone production. ASF was less potent (ED50 = 10(-9) M) than ACTH but was more potent than beta-LPH. When ASF was added to the incubation with low dose of A II or ACTH, its effect on aldosterone production was additive, while no additional effect of ASF on aldosterone production was obtained in the presence of high dose of A II or ACTH. ASF increased the conversion of corticosterone to aldosterone like ACTH and beta-LPH. We have reported that ASF is a true aldosterone secretagogue and readily distinguishable from ACTH, A II and beta-LPH. The present study suggests ASF shares a common rate-limiting final pathway of steroidogenesis, which may be the step between corticosterone to aldosterone, with ACTH, A II and beta-LPH.
D000311:Adrenal Glands / Q000378:metabolism; D000324:Adrenocorticotropic Hormone / Q000494:pharmacology; D000450:Aldosterone / Q000096:biosynthesis / Q000378:metabolism* / Q000494:pharmacology*; D000804:Angiotensin II / Q000494:pharmacology; D006023:Glycoproteins; D006801:Humans; D008077:Lipoproteins, LDL / Q000494:pharmacology; D011506:Proteins / Q000494:pharmacology*
D006023:Glycoproteins; D008077:Lipoproteins, LDL; D011506:Proteins; C028798:aldosterone stimulating factor, human; D000804:Angiotensin II; D000450:Aldosterone; D000324:Adrenocorticotropic Hormone