Angiotensin II exerts its effect on aldosterone production and potassium permeability through receptor subtype AT1 in rat adrenal glomerulosa cells.
The stimulatory effect of angiotensin II (AT) on the accumulation of inositol phosphates and on aldosterone production is abolished by the AT1 selective receptor antagonist DuP753 while PD123177, an AT2 antagonist, is ineffective. Similarly, a depolarizing effect of AT (inhibition of K+/86Rb efflux) is prevented by DuP753. While mediators derived from phospholipase C activation have a central role in the stimulation of aldosterone production by AT, the effect of AT on K+ permeability is mimicked neither by elevation of cytoplasmic [Ca2+] by ionomycin nor by kinase C activation with phorbol ester. Our results suggest that AT stimulates phospholipase C and the subsequent steroid production by glomerulosa cells through AT1 receptors. In addition some events induced by the activation of AT1 receptors may not be mediated by the activation of phospholipase C.
Hajnóczky
G
G
Department of Physiology, Semmelweis University Medical School, Budapest, Hungary.
Csordás
G
G
Bagó
A
A
Chiu
A T
AT
Spät
A
A
D000450:Aldosterone / Q000096:biosynthesis*; D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002463:Cell Membrane Permeability / Q000187:drug effects; D002478:Cells, Cultured; D005260:Female; D011188:Potassium / Q000378:metabolism*; D015221:Potassium Channels / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D011945:Receptors, Angiotensin / Q000187:drug effects; D015384:Zona Glomerulosa / Q000187:drug effects*
D015221:Potassium Channels; D011945:Receptors, Angiotensin; D000804:Angiotensin II; D000450:Aldosterone; D011188:Potassium; D002118:Calcium