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