铁皮石斛水煎提取产物保护异丙肾上腺素诱导的心肌肥厚的研究

Protective Effect of Dendrobium Candidum Aqueous Extract on Isoproterenol Induced Cardiac Hypertrophy in Rats

目的:以异丙肾上腺素(ISO)诱导心肌肥厚模型,观察铁皮石斛水煎提取物的作用并探讨其作用机制。方法:健康SD大鼠70只,雌雄各半,随机分为5组,每组14只;即正常组,模型组,铁皮石斛水煎提取物治疗组(低、中、高剂量),对应生药含量为0.09g/kg,0.18g/kg,1.10g/kg。除正常组外,其余各组每天背部皮下注射ISO(2mg/kg),连续10d,治疗组给予不同剂量的铁皮石斛样品共30d,模型组给予同等量的生理盐水。颈总动脉插管检测各组左心室收缩压(LVSP),计算左心室(LVW)/胫骨长、心脏重量指数(HWI);心肌组织HE染色观察心肌结构,MASSON染色观察心肌纤维化程度;酶联免疫分析(ELISA)检测血浆中心房利钠肽(ANP)、脑钠肽(BNP)、心肌肌钙蛋白I(cTn-I)浓度。结果:与正常组比较,ISO诱导大鼠心肌肥厚明显,且血浆中ANP、BNP和cTn-I的水平显著上升(P<0.05);与模型组比较,铁皮石斛水煎液能显著抑制ISO诱导的心室压力升高(P<0.05)和心室肥厚,改善心肌纤维化,减少心肌胶原合成(P<0.05),同时显著下调血浆ANP、BNP和cTn-I的水平(P<0.05)。结论:铁皮石斛水煎提取物对异丙肾上腺素诱导的心肌肥厚具有保护作用。

Objective:To study the effect of Dendrobium candidum aqueous extracton isoproterenol-induced myocardial hypertrophy in rats and its mechanism.Methods:Totally 70 SD rats,male and female half,were randomly divided into five groups (n=14),including normal group,model group,three therapy groups with different doses of Dendrobium candidum water extract (low,medium,high dose),and the corresponding crude drug content was 0.09 g/kg,0.18 g/kg and 1.10 g/kg..Except the normal group,rats of other groups were injected back subcutaneously with ISO (2 mg/kg) for 10 consecutive days.At the same time as the injection of ISO,preventive administration groups were given different doses of the sample for 30 days and model group were given physiological saline.Left ventricular systolic pressure is measured in each group.The left ventricle (LW)/ tibia long and heart weight index were calculated.HE staining and masson staining in myocardial tissues were used to observe the myocardial structure and the degree of myocardial fibrosis.Atrial natriuretic peptide (ANP),Brain natriuretic peptide (BNP) and cardiac troponin I (cTN-I) concentration were measured by enzyme-linked immunosorbent assay (ELISA).Results:Compared with the normal group,the levels of ANP,BNP and cTN-I in plasma were significantly increased in ISO-induced hypertrophic rats (P<0.05);Compared with the model group, Dendrobium candidum can inhibit ISO-induced ventricular pressure (P<0.05) and ventricular hypertrophy,reduce myocardial collagen synthesis (P<0.05) and down regulate plasma ANP,BNP and cTn-I levels.Conclusion:Dendrobium candidum aqueous extract has a protective effect on isoproterenol-induced cardiac hypertrophy.