Genetic manipulation of the renin-angiotensin system

The renin-angiotensin system is widely known for its importance in control of blood pressure, electrolyte homeostasis and volume regulation, Recently, renin-angiotensin system function was studied using homologous recombinati on in embryonic stem cells to manipulate the mouse genome. Angiotensinogen, angiotensin-converting enzyme and angiotensin II receptors were each elimi nated in separate lines of mice, These null animals share similar phenotype s, such as a lowering of blood pressure, abnormal renal development, malfun ction of the kidney and, unexpectedly, a decrease in hematocrit. In additio n, angiotensin-converting enzyme null male mice sire far smaller litters th an male wild-type mice. This suggests an unexplored role for angiotensin-co nverting enzyme in conception. Future studies with these and other genetica lly engineered mice lines will reveal novel physiological effects of angiot ensin II. Curr Opin Nephrol Hypertens 10:483-491. (C) 2001 Lippincott Willi ams & Wilkins.