Effect of simvastatin on myocardial hypertrophy and expression or extracellular signal-regulated Kinases in spontaneously hypertensive rats

OBJECTIVE To explore the effect of simvastatin on myocardial hypertrophy and the expression of extracellular signal-regulated kinases (ERK) in spontaneously hypertensive rat (SHR). METHODS Fourteen 14-week-age SHRs were randomizedly divided into 2 groups. One group was given ig simvastatin 40 mg·kg~(-1)·d~(-1) for 10 weeks, while the other SHR group (control) and 7 Wistar Kyoto rats (WKY) were routinely given ig vehicle (0.5% carboxymethyl cellulose) for 10 weeks. The ratio of left ventricle weight to body weight(LVW/BW) was measured to reflect myocardial hypertrophy. The total ERK expression (t-ERK), phosphorylated-ERK (p-ERK) and mitogen-activated protein kinase phophatase-1 (MKP-1) in myocardial tissue were studied by Western-blot analysis. RESULTS The ratio of LVW/BW in SHR group with treated simvastatin decreased significantly than that in control group(P0.05). There was no significant difference of t-ERK expression among 3 groups(P0.05). The level of p-ERK and the ratio of p-ERK/t-ERK in SHR group were treated with simvastatin significantly lower than that in control group(P0.01), and similar to that in WKY group. MKP-1 expression of simvastatin group was lower than that in control group (P0.05). There was no significant difference in MKP-1 expression between the simvastatin group and WKY group. CONCLUSION Simvastatin can inhibit ERK activation so as to result in the regression of myocardial hypertrophy in SHR.