Losartan alleviates hyperuricemia-induced atherosclerosis in a rabbit model.

OBJECTIVE To investigate the mechanisms underlying the therapeutic effects of losartan on hyperuricemia-induced aortic atherosclerosis, in an experimental rabbit model. METHODS Male rabbits (n = 48) were divided into control, hyperuricemia (HU), hypercholesterolemia + hyperuricemia (HC + HU) and high-purine with 30-mg/kg/d losartan (HU + losartan) groups. Serum uric acid (UA) and plasma renin and angiotensin II activities were determined. Aortic tissue specimens were analyzed for histological changes and proliferating cell nuclear antigen (PCNA). Liver tissues were sampled for quantitative analyses of liver low-density lipoprotein receptor (LDLR) mRNA and protein via reverse transcription polymerase chain reaction and western blotting. RESULTS After 12 weeks, serum UA and plasma renin and plasma angiotensin II activities were enhanced in the HU and HU + HC groups (P < 0.001) compared to the control, whereas in the HU + losartan group plasma renin activity was not different and serum UA concentrations as well as plasma angiotensin II activity were moderately enhanced (P < 0.05). Smooth muscle cell (SMC) PCNA expression increased strongly in the HU and HU + HC groups (P < 0.001), but was less pronounced in the HU + losartan group. In contrast, transcription and expression of LDLR mRNA and protein were significantly higher in the control and HU + losartan groups compared to the HU and HU + HC groups. Both the HU and HU + HC groups had elevated intima thickness and intima areas compared to the control and HU + losartan groups. CONCLUSIONS Losartan can alleviate experimental atherosclerosis induced by hyperuricemia.