P-360: Renin release in response to renin system blockade: further evidence for activation of the intrarenal renin system in type-1 diabetes mellitus

In type-1 diabetics, Captopril (Cap) and Candesartan (Cande) administration results in a supra normal rise in renal plasma flow (RPF), thought to reflect activation of the intrarenal renin angiotensin system (RAS). Because of implications for diabetic nephropathy, we explored, in 43 type-1 diabetics (D) (27.7 ± 1.5) and 34 normal subjects (NL) (37.7 ± 2.7 years) in high salt balance, the control of renin response to blockade of the RAS with 25 mg of Cap and 16 mg of Cande on consecutive days. All were white with normal renal function. Baseline PRA was higher in D 0.6 ± 0.08 vs NL 0.4 ± 0.06 ng/mLAngI/hr, (p< 0.001). After Cap, PRA peaked after 90 mn to 5.9 ± 1 in D and 1.6 ± 1 ng/mLAngI/hr in NL (p< 0.001). Baseline PRA was positively correlated with peak PRA in D (r= 0.682, p= 0.0012), and in NL (r= 0.843, p