Effects of simvastatin on activities of endogenous antioxidant enzymes and angiotensin-converting enzyme in rat myocardium with pressure-overload cardiac hypertrophy.

Aim: To investigate effects of simvastatin (Sim) on the activities of antioxidant enzymes and angiotensin-converting enzyme in rat myocardium with pressure-overload cardiac hypertrophy.

Methods: Left ventricular hypertrophy (LVH) was induced by partly constricting rat abdominal aorta between the left and right renal artery. Rats were given ig Sim 1.8 and 3.6 mg . kg-1 . d-1 for 8 weeks following 6 weeks aortic constriction. Activities of antioxidant enzymes and angiotensin-converting enzyme, and lipid peroxidation of left ventricular (LV) tissue were determined.

Results: Contents of angiotensin II and thiobarbituric acid reactive substances (TBARS), and activity of ACE in LVH group (n = 8) were increased by 163 %, 90 %, and 130 %, respectively (P < 0.01)compared with sham-operated group (n = 7), and were decreased by 30 %, 37 %, and 51 %, respectively (P < 0.01) in high dosage Sim treatment group (n = 9) compared with LVH group. Activities of catalase and glutathione peroxidase of LV tissue in LVH group were decreased by 29 % and 23 % (P < 0.01) compared with sham-operated group, and were increased by 32 % and 22 % (P < 0.01) in high dosage Sim treatment group compared with LVH group. Activity of Cu, Zn-superoxide dismutase (SOD) of LV tissue was increased by 33 % in LVH group compared with sham-operated group. Sim treatment did not significantly affect activity of Cu,Zn-SOD.

Conclusion: Alteration of redox status in myocardium is associated with cardiac hypertrophy and inhibitory effects of Sim on cardiac hypertrophy in rats model might be linked to its antioxidant effects.