Combination of hypercholesterolemia and hypertension augments renal function abnormalities

Hypercholesterolemia and hypertension are both risk factors for end-stage renal disease. This study was designed to examine whether their coexistence augmented impairment in renal function and redox status. Regional renal hemodynamics and function in response to vasoactive challenges with acetylcholine or sodium nitroprusside were quantified by using electron-beam computed tomography in pigs after 12 weeks of either a normal (n=10) or hypercholesterolemic (n= 10) diet, renovascular hypertension (n=7), or combined hypercholesterolemia+hypertension (n=6). The hypercholesterolemic and hypercholesterolemic+hypertensive groups had significantly increased serum cholesterol levels, whereas in the hypertensive and hypercholesterolemic+hypertensive groups, mean arterial pressure was significantly elevated compared with the group fed a normal diet. Basal regional renal perfusion and glomerular filtration rates were similar among the groups. In response to acetylcholine, cortical perfusion increased in normal animals (15.6±4.7%, P=0.002) but not in hypercholesterolemic or hypertensive animals (8.0±7.4% and 8.2±5.9%, respectively: P>0.05). Moreover, in the hypercholesterolemic+hypertensive group, cortical perfusion response was further attenuated (2.5±4.8%, P=0.02) and significantly different from the group fed a normal diet (P