Abstract
The purpose of this study was to explore the effect of polydatin on ventricular remodeling
after myocardial infarction in coronary artery ligation rats and to elucidate the
underlying mechanisms. A rat model of ventricular remodeling after myocardial infarction
was established by left coronary artery ligation. Rats with coronary artery ligation
were randomly divided into five groups: control, plus 40 mg/kg captopril, plus 25 mg/kg
polydatin, plus 50 mg/kg polydatin, and plus 100 mg/kg polydatin. The sham-operated
group was used as a negative control. Rats were administered intragastrically with
the corresponding drugs or drinking water for seven weeks. At the end of the treatment,
the left ventricular weight index and heart weight index were assessed. The cross-sectional
size of cardiomyocytes was measured by staining myocardium tissue with hematoxylin
and eosin. Collagen content was counted by Sirius red in aqueous saturated picric
acid. The concentrations of angiotensin I, angiotensin II, aldosterone, and endothelin
1 in myocardium or serum were determined by radioimmunoassay. Hydroxyproline and nitric
oxide concentrations and glutathione peroxidase and catalase activities in serum were
measured by ultraviolet spectrophotometry. Our results showed that seven weeks of
polydatin treatment resulted in a significantly reduced left ventricular weight index,
heart weight index, serum concentrations of hydroxyproline and aldosterone, an increased
concentration of nitric oxide as well as enhanced activities of glutathione peroxidase
and catalase. Myocardial angiotensin I, angiotensin II, and endothelin 1 levels were
also reduced. The cardiomyocyte cross-sectional area and collagen deposition diminished.
This study suggests that polydatin may attenuate ventricular remodeling after myocardial
infarction in coronary artery ligation rats through restricting the excessive activation
of the renin-angiotensin-aldosterone system and inhibiting peroxidation.
Key words
polydatin - myocardial infarction - ventricular remodeling - coronary artery ligation
- renin-angiotensin-aldosterone system - peroxidation