REN and Hypertension: Consistent with the renin-angiotensin system playing a role in mediating the hypertension in programming, studies have shown that both captopril, an angiotensin converting enzyme inhibitor, and losartan, an angiotensin II receptor blocker, administered to the drinking water from 2–4 weeks resulted a reduction in blood pressure to levels comparable to the rats whose mothers were fed a normal protein diet [16,17].