茶多酚对低氧肺动脉高压大鼠Smac表达的影响

Effects of tea polyphenols on the expression of Smac in rats with pulmonary hypertension induced by hypoxia

目的:探讨茶多酚在预防肺动脉高压中的作用及可能机制。方法:24只雄性SD大鼠随机分为对照组、肺动脉高压组和茶多酚组,后两组置于低氧舱内4周,每组各8只。每日低氧前茶多酚组予茶多酚200mg/(kg·d)灌胃,对照组、肺动脉高压组予等量生理盐水灌胃。比较各组平均肺动脉压(mPAP)、右心室肥厚程度、肺小动脉管壁厚度,及肺动脉平滑肌细胞(PASMC)凋亡、肺组织Smac mRNA表达水平。结果:茶多酚显著降低mPAP,减轻右心室肥厚、肺小动脉管壁厚度,上调Smac基因表达,促进PASMC凋亡(P<0.01或P<0.05)。结论:茶多酚预防肺动脉高压可能是通过促进Smac基因表达,促进PASMC凋亡来实现的。

Objective To investigate the roles of tea polyphenols play in puhnonary arterial hypertension and the mechanism. Methods 24 male Sprague Dawley rats were randomly divided into control group, pulmonal7 hypertension group and tea polyphenols group （each n=8）, rats in the pulmonary hypertension group and tea polyphenols group were placed into a hypoxic chamber for 4 weeks, rats in the tea polyphenols group was treated with tea polyphenols [200 mg/（kg＇d）l by garage before hypoxia, and those in the control group and pulmonary hypertension group received equivalent saline by garage. Then the mean pulmonary artery pressure （mPAP）, the index of the right ventricular hypertrophy and the wall thickness of small pulmonary artery, the apoptosis of pulmonary artery smooth muscle cell （PASMC）, and the expressions of Smac mRNA in lung tissue were detected. Results Tea polyphenols could significantly decrease the mPAP, the hypertrophy of right ventricule and the thickness of small pulmonary artery wall, and promote Smac mRNA expression in lung tissue and the apoptosis of PASMC （P 〈 0.01 or P 〈 0.05）. Conclusion Tea polyphenols could prevent pulmonary hypertension which may be linked with the promotion of Smac expression and the apoptosis of PASMC.