The pituitary-adrenal axis and the renin-angiotensin system in treated congenital adrenal hyperplasia

Abstract

41 out-patients, treated for 21-hydroxylase deficiency with oral cortisol (15 mg-30 mg/m2), were studied at regular intervals. Among them were 24 salt-losers, who, in addition to cortisol,received 9 α-flurocortisol (20 μg-100 μg), and 17 non salt-losers. In the 1st group, plasma ACTH, 170HP aldosterone and renin activity were (geometric mean) : 99.8 pg/ml, 28.8 ng/ml, 14.6 pg/ml and 8.4 ng/ml/h respectively. In the 2nd group, these values were 69 pg/ml, 57.9 ng/ml, 33.5 pg/ml and 2.3 ng/ml/h. There was no difference in ACTH mean levels, while 170HP was significantly lower in the first group (p < 0.05). However, when choosing from the two groups the patients with similar 170HP values, ACTH was found to be higher in the salt-losers, 126.9 pg/ml against 67 pg/ml in the non salt-losers (p < 0.02). These data suggest an inhibiting effect of angiotensin II (A II), at high concentrations, on the pattern of glucocorticoid synthesis, as has already been reported in man. Furthermore, we have noted that in isolated guinea pig adrenal cells, the cortisol output provoked by ACTH stimulation is decreased by the addition of A II.