Role for aldosterone in blood pressure regulation of obese adolescents.
To determine the role of aldosterone in the regulation of blood pressure (BP) in obese adolescents, supine and 2-hour upright plasma renin activity (PRA), and aldosterone and cortisol were measured in 10 nonobese and 30 obese adolescents before and after a 20-week weight loss program. The obese adolescents had significantly higher supine and 2-hour upright plasma aldosterone concentrations (17 +/- 8 vs 6 +/- 2 ng/dl [p less than 0.01 supine obese vs nonobese] and 30 +/- 11 vs 14 +/- 8 ng/dl [p less than 0.01 2-hour upright]). Although PRA was not significantly different between the 2 groups of children, a given increment in PRA produced a greater increment in aldosterone in the obese adolescents. In addition, obese subjects had a significantly increased mean BP (93 +/- 12 vs 74 +/- 8, p less than 0.005) and a weak correlation between BP and plasma aldosterone concentration. Compared with an obese control group, weight loss resulted in a significant decrease in plasma aldosterone (p less than 0.01) without an associated decrease in PRA. After weight loss there was also a significant decrease in the slope of the posture-induced relation between PRA and aldosterone. In addition to weight loss being associated with a significant decrease in BP (p less than 0.01), there was a significant correlation between the change in plasma aldosterone and the change in mean BP (r = 0.538; p less than 0.002 change in upright aldosterone vs change in mean BP). Obese adolescents have an increased plasma aldosterone concentration that may be important in the regulation of their BP.
D000293:Adolescent; D000450:Aldosterone / Q000097:blood / Q000502:physiology*; D001794:Blood Pressure; D001835:Body Weight; D002648:Child; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D009765:Obesity / Q000503:physiopathology*; D011187:Posture; D012083:Renin / Q000097:blood; D012084:Renin-Angiotensin System
D000450:Aldosterone; D012083:Renin; D006854:Hydrocortisone