Effect of Probucol and Irbesartan on Blood Pressure and Serum Level of Plasminogen Activator Inhibitor-1 in Spontaneously Hypertensive Rats

Objective To investigate the effect of antioxidant probucol and irbesartan on blood pressure and serum level of plasminogen activator inhibitor-1 (PAI-1) in spontaneously hypertensive rats (SHR). Methods Fourty SHR were divided into four groups and treated with placebo (SHR-C group),probucol [61 mg/(kg·d) (SHR-Pro group),irbesartan[50 mg/(kg·d)(SHR-Irb group) or combination of both drugs (SHR-Pro+Irb group) by gavaging for 12 weeks. Blood pressure was measured using tail cuff method. Serum PAI-1 level was measured by ELISA. Results ① No difference in blood pressure was detected among animals in different treated groups before treatment (P0.05). No difference of blood pressure was noted between groups treated with Pro and controls. After treatment,the blood pressure of rats in SHR-Irb group and SHR-Pro+Irb group were significantly lower as compared to that of the SHR-C group(P0.01). Mice in SHR-Pro+Irb group had lower blood pressure than that of SHR-Irb group(P0.05). ② Serum PAI-1 levels in the four SHR groups were higher than that of WKY group(SHR-C:P0.05,SHR-Pro,SHR-Irb,SHR-Pro+Irb:P0.01). Serum PAI-1 level in SHR-Irb,SHR-Pro+Irb groups were lower than that of SHR-C group(P0.01). Conclusion Probucol alone does not decrease the blood pressure in SHR. In combination with irbesartan it shows an antihypertensive effect. Irbesartan alone can decrease the blood pressure and the serum PAI-1 level in SHR.