title: Studies of the control of plasma aldosterone concentration in normal man. 3. Response to sodium chloride infusion.
abstract: The peripheral plasma levels of aldosterone, renin activity, potassium, sodium, corticosterone, and cortisol were measured in six normal subjects four times daily-10 a.m., 2 p.m., 5 p.m., 11 p.m.-on 3 consecutive days. A constant daytime activity program was maintained throughout the study. After 5 days on a 10 mEq sodium/100 mEq potassium isocaloric intake, the mean upright 10 a.m. plasma renin activity was 1773+/-186 ng/100 ml per 3 hr and the mean plasma aldosterone, 81+/-14 ng/100 ml. These two parameters fell continuously throughout the day parallel to the fall in plasma cortisol and corticosterone. In response to 2 liters of normal saline infused from 10 a.m. to 2 p.m. on 2 consecutive days, plasma aldosterone levels fell significantly to 13+/-5 ng/100 ml at 2 p.m. after the 1st day's infusion and to 6+/-1 ng/100 ml at 2 p.m. after the 2nd. Plasma renin activity demonstrated a parallel fall to 368+/-63 ng/100 ml per 3 hr and 189+/-27 ng/100 ml per 3 hr at 2 p.m. on the 1st and 2nd days, respectively. There was no significant alteration in plasma levels of cortisol, corticosterone, potassium, or sodium on the 2 days of sodium loading in comparison with the control day. In an additional study, five normal supine subjects received 500 ml saline/hr for 6 hr. As in the 2 day study, plasma aldosterone and renin activity had parallel decrements at 1, 2, 4, and 6 hr after the start of the saline infusion. From these studies, it is concluded that plasma renin activity is the dominant factor controlling plasma aldosterone when sodium-depleted normal subjects are acutely repleted.
mesh_terms: D000328:Adult; D000450:Aldosterone / Q000097:blood*; D003345:Corticosterone / Q000097:blood; D004032:Diet; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007263:Infusions, Parenteral; D007700:Kinetics; D008297:Male; D011188:Potassium / Q000097:blood; D012083:Renin / Q000097:blood / Q000502:physiology; D012964:Sodium / Q000097:blood; D012965:Sodium Chloride / Q000008:administration & dosage / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D012965:Sodium Chloride; D000450:Aldosterone; D012964:Sodium; D012083:Renin; D011188:Potassium; D003345:Corticosterone; D006854:Hydrocortisone