Effect of Atrial Natriuretic Factor on Aldosterone and Its Precursor Steroid Production in Adrenal Zona Glomerulosa Cells from Spontaneously Hypertensive Rats

ABSTRACT

The effect of α-human atrial natriuretic factor(α-hANP, 10^-6M- 10^-8M) on basal, and maximum angiotensin II (AII, 4. 8 x 10^-8 M)-, ACTH (4. 3 × 10^-9M)-, and potassium (8mM)-stimulated levels of corticosterone, 18-hydroxycorticosterone (18-OHB) and aldosterone production were studied in adrenal glomerulosa cells from spontaneously hypertensive rats (SHR) at 14 weeks of age as compared to those in the age-matched Wistar-Kyoto rats (WKY) on a normal sodium diet. Plasma corticosterone, 18-OHB and aldosterone levels and the aldosterone response in vitro to the graded doses of All were similar in SHR and WKY. Basal, and maximum All-, ACTH-, and potassium- stimulated levels of corticosterone, 18-OHB and aldosterone also were similar in the cells from SHR and WKY. Q-hANP similarly inhibited basal and stimulated levels of these corticosteroids in the cells from SHR and WKY.

These results indicate that the inhibitory effect of α-hANP on aldosteronogenesis is unaltered in SHR at 14 weeks of age on a normal sodium diet.