中药X方剂对7d尾部悬吊大鼠心血管脱锻炼的对抗效应

Anti-effects of X-prescription on Cardiovascular Deconditioning in Rats after 7 d Tail Suspension

目的揭示模拟失重大鼠心血管脱锻炼病理生理学变化;探索中药X方剂对抗模拟失重大鼠心血管脱锻炼的效应。方法-30°7d尾部悬吊模拟失重的生理效应。雄性Wistar大鼠被随机分成3组:自由活动对照组(Con)、7d尾部悬吊组(TS7)和7d尾部悬吊用药组(TS7+X-方剂)。头向上倾斜90°60min模拟立位应激时的生理效应。TS7+X-方剂组用X-方剂灌胃给药,其它组灌注等量的生理盐水。PowerLab生理记录系统检测模拟立位60min颈动脉压、Ⅱ导心电,记录胸主动脉流量,分析计算心率、平均动脉压、每搏指数、心指数和总外周阻力。结果TS7大鼠模拟立位期间心率和总外周阻力升高不足,平均动脉压、每搏指数和心指数降低更明显;TS7+X-方剂组大鼠以上变化得到不同程度的改善。结论TS7组大鼠出现心血管脱锻炼,X-方剂能较好改善TS7大鼠心血管脱锻炼作用,与其改善颈-心反射和外周阻力贮备有关,其作用机理有待进一步研究。

Objective To disclose the patho-physiological changes of cardiovascular deconditioning （CVD） induced with tail-suspension （TS） and to explore the anti-effects of X-prescription on CVD in TS rats. Methods -30°tail-suspended rats were used as the model to simulate the physiological effects of weightlessness. Wistar rats were randomly arranged into：control group （Con）,7 d TS group （ TS7） and TS7 ＋ X-prescription group （ TS7 ＋ X-prescription）. All the rats were subjected to ＋ 90°head-up tilt to simulate the physiological effects of orthostatic stress （SO） after 7d tail-suspension . The rats of TS7 ＋ X-prescription group were given X-prescription with stomach tube and the other rats done 0.9% isometric saline. Carotid pressure and limb II ECG were measured with a Power Lab physiological system. The stroke volume of thoracic aorta was done with a Transonic system during 60 min tilt. Heart rate （ HR）, mean arterial pressure （ MAP）, stroke volume index （SVI）, cardiac output index（COl） and total peripheral resistance（TPR） were analyzed. Results The increases of HR and TPR were deficient, and the MAP, SVI and COl decreased in the TS7 rats more obviously than the Con rats during SO. These changes were effectively alleviated in the TS7 ＋ X-prescription rats. Conclusion An obvious CVD could be induced with SO in the TS7 rats. The X-prescription could effectively alleviate the CVD in the TS7 rats, which might be due to improving the reservation of peripheral resistance and carotid baro-receptor cardiac reflex. The mechanisms will be further studied.