[Effect of total phenolic part of Rhus chinensis against myocardial ischemia in mice]

Rhus chinensis is an important resource plant. The aqueous extract of R. chinensis roots or stems was to produce Shuguantong Syrup, which is mainly used for the treatment of coronary heart disease and angina pectoris with definite curative effect. On this basis, the crude phenolic part of R. chinensis prepared by macroporous resin was evaluated for the cardio protective effect against myocardial ischemia in mice. The results showed that the phenolic part group with oral administration at the dosages of 190.8-381.6 mg·kg~(-1), compared with the model group, reduced the values of left ventricular end systolic diameter(LVEDs) and the left ventricular end diastolic diameter(LVEDd), and increased the cardiac ejection fraction(EF) and left ventricular fractional shortening(FS) rate, which could effectively improve cardiac function and exert its anti-myocardial ischemia effect, and reduce the rising levels of creatine kinase isoenzyme(CK-MB) and lactate dehydrogenase(LDH) in serum. HE staining showed that the phenolic part group reduced the infiltration of myocardial inflammatory cells and alleviated the degree of myocardial fibrosis and collagen deposition. TUNEL staining showed that the blue-green fluorescence of the phenolic part group decreased successively, and the degree of myocardial cell apoptosis was reduced. Immunohistochemical staining suggested that it could reduce the number of positive cells for p53 protein expression and significantly improve myocardial cell damage. All above data suggested that the phenolic part group had an anti-mycardial ischemis effect. Related mechanism studies revealed that the crude phenolic part could regulate the expressions of the p53 gene(p53), Bcl-2-associated X protein(Bax), B lymphoma-2 gene(Bcl-2), and caspase-3 protein(caspase-3) in myocardial tissue, suggesting that it could reduce cardiac remodeling and myocardial ischemic damage, and improve cardiac function by inhibiting myocardial apoptosis.This research laid a foundation for the elucidation of the pharmacological ingredients R. chinensis.