Body mass index and angiotensin-dependent control of the renal circulation in healthy humans.
Obesity is increasingly recognized as a risk factor for renal disease, but the mechanism is unclear. Renal plasma flow response to captopril, as an index of renin-angiotensin system activity, was measured by para-aminohippurate clearance technique in 100 healthy, normotensive subjects in balance on a high-salt diet. Of the 100 subjects, body mass index exceeded 25 in 56 and exceeded 30 in 22. The average vasodilator response to captopril was 27+/-7 mL/min per 1.73 m2 (P<0.0001). After adjustment for other predictors of the renal plasma flow response to captopril using a multivariate linear regression model, there was a highly significant relationship between age- and plasma renin activity-adjusted body mass index and the renal plasma flow response to captopril; however, a quadratic model provided a substantially better fit (r=0.55; P<0.0001; P=0.03 versus linear correlation). The strong association between increasing body mass index and angiotensin-dependent control of the renal circulation suggests that this may be a mechanism by which obesity contributes to renal disease. Weight loss should be considered in the overweight or obese patient for renal protection.
Ahmed
Sofia B
SB
Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA. sahmed7@partners.org
Fisher
Naomi D L
ND
Stevanovic
Radomir
R
Hollenberg
Norman K
NK
D000328:Adult; D000375:Aging / Q000502:physiology; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology; D000809:Angiotensins / Q000502:physiology*; D015992:Body Mass Index; D002216:Captopril / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012016:Reference Values; D012079:Renal Circulation / Q000187:drug effects / Q000502:physiology*; D012083:Renin / Q000097:blood; D017673:Sodium Chloride, Dietary / Q000008:administration & dosage / Q000494:pharmacology; D014664:Vasodilation
D000806:Angiotensin-Converting Enzyme Inhibitors; D000809:Angiotensins; D017673:Sodium Chloride, Dietary; D002216:Captopril; D012083:Renin