Objective To investigate the interventional effects of pretreatment with total polyphenols extracted from Toona sinensis Roem on the injury induced by myocardial ischemia-reperfusion in rats. Metlods Fifty SD rats were randomly divided into 5 groups: sham operation group, model group and 3 pretreatment groups in which the rats were treated with total polyphenols in 3 different doses. Rats in sham operation and model group were treated with 5 sodium carboxy methyl cellulose, and in 3 pretreatment groups the rats were treated with 50, 100 and 200mg/kg of total polyphenols, respactively, by gavage for 7 days, and then the myocardial ischernia/reperfusion injury was induced by ligating the left coronary artery (LAD) for 30min followed by a 120 min reperfusion in anesthetized rats. Rats in sham operation group were operated with placing the ligature but without ligating. ECGs were recorded before and 30 min after ligating LAD,and 30, 60 and 90min after reperfusion. The levels of J point at different time were observed and compared. After reperfusion, the blood was collected from abdominal aorta to prepare serum samples. The activity of CK, the level of cTnI, TXB2 and 6-keto-PGF1a in serum were then determincd. Finally, the hearts of rats below the ligature were cut into 5 slices and stained with 1％ TTC for 15 min, the extent of myocardial infarction was calculated. Results Compared with that in sham operation group, the J point of ECG elevated obviously in model group, the activity of serum CK and the contents of cTnI and TXB2 increased markedly, while the 6-keto-PGF1a level declined significantly (P＜0.05), and notable myocardial infarction was apparent. Compared with those in model group, the height of J point descended, the activity of CK and the level of cTnI and TXB2 in serum decreased, while the level of 6-keto-PGF1a increased, and the degree of myocardial infarction was alleviated in the 3 pretreatment groups. All the data were found to have statistically significant differences.Conclusion Total polyphenols extracted from Toona sinensis Roem may play an interventional effect on the injury induced by myocardial ischemia/reperfusion of rats.%目的 观察香椿子总多酚预处理对大鼠心肌缺血再灌注损伤是否具有干预作用.方法 50只SD大鼠随机均分成5组(n=10):假手术组,模型组,香椿子总多酚预处理低、中、高剂量组,后3组分别给予香椿子总多酚50、100、200mg/kg,假手术组和模型组分别给予等体积5‰羧甲基纤维素钠,各组均灌胃给药7d.灌胃结束后,模型组和香椿子总多酚预处理组采用左冠状动脉前降支结扎30min再灌120min的方法复制大鼠心肌缺血再灌注损伤模型,假手术组只穿线不结扎.记录冠脉结扎前、结扎后30min及再灌注30、60、90min心电图,比较各组大鼠心电图J点抬高的程度.再灌注结束时腹主动脉取血,测定血清中磷酸肌酸激酶(CK)活力,肌钙蛋白I(cTnI)、血栓素B2 (TXB2)和6-酮-前列腺素F1α (6-keto-PGF1α)含量.最后,取出心脏,自结扎线以下平行均匀切成5片,用1%氯化三苯基四氮唑(TTC)染色15min,测定心肌梗死程度.结果 与假手术组比较,模型组大鼠的心电图J点显著抬高,血清中CK活力和cTnI、TXB2含量显著升高,6-keto-PGF1α水平显著下降(P<0.05),出现了明显的心肌梗死.与模型组相比,香椿子总多酚各预处理能显著降低心肌缺血再灌注大鼠心电图J点抬高的程度,降低血清中CK活力及cTnI、TXB2含量,升高血清中6-keto-PGF1α水平,减轻心肌梗死程度,差异具有统计学意义(P<0.05).结论 香椿子总多酚预处理对大鼠心肌缺血再灌注损伤具有干预作用.
展开▼
