Effects of corticosteroids on cytosolic free calcium concentration of the rat adrenal zona glomerulosa cell.
In the perfused cells isolated from the rat adrenal zona glomerulosa, deoxycorticosterone, aldosterone and dexamethasone (10 microM-1 mM) significantly inhibited elevation of the cytosolic concentration of calcium ion [Ca2+]c caused by a preceding stimulation with angiotensin II (ANG II) or high K+. The inhibition of [Ca2+]c was observed within a few minutes after application of the corticosteroids. The resting level of [Ca2+]c was reduced by aldosterone, whereas it was not significantly altered by deoxycorticosterone or dexamethasone. Since it is well established that the elevation of [Ca2+]c is required for the secretory responses to ANG II or high K+, the present results are compatible with a view that aldosterone secretion from the cortical cells in response to the secretagogues may, in turn, be attenuated by corticosteroids, including aldosterone itself.
Department of Physiology, Niigata University School of Medicine, Japan.
K
K
Yamaguchi
Y
Y
Habara
A
A
Warashina
T
T
Kanno
D000450:Aldosterone / Q000494:pharmacology*; D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000032:analysis*; D003900:Desoxycorticosterone / Q000494:pharmacology*; D003907:Dexamethasone / Q000494:pharmacology*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D015384:Zona Glomerulosa / Q000737:chemistry / Q000187:drug effects*
D000804:Angiotensin II; D003900:Desoxycorticosterone; D000450:Aldosterone; D003907:Dexamethasone; D002118:Calcium