帕瑞昔布钠对急性心肌梗死大鼠心功能的影响

目的 评价帕瑞昔布钠对急性心肌梗死大鼠心功能的影响.方法 成年雄性SD大鼠24只,体重230～250 g,随机分为3组(n=8):假手术组(S组)、急性心肌梗死组(AMI组)和帕瑞昔布钠组(P组).AMI组和P组采用结扎左冠状动脉前降支的方法制备大鼠急性心肌梗死模型,S组冠状动脉穿线但不结扎;24 h后P组腹腔注射帕瑞昔布钠8 mg/kg,1次/d,连续3 d,AMI组用生理盐水替代.术后第4天测定并记录左心室收缩压(LVSP)、左心室舒张末期压(LVEDP)、左心室收缩压最大上升速率(+dp/dtmax)和左心室收缩压最大下降速率(-dp/dtmax);采集颈总动脉血样3 ml,采用放射免疫法测定血浆血栓素A2(TXA2)和前列腺素I2(PGI2)的浓度,并计算PGI2/TXA2;采血后取左心室心肌组织,测定梗死面积,计算心肌梗死体积.结果 与S组比较,AMI组和P组LVSP、±dp/dtmax、血浆PGI2浓度和PGI2/TXA2降低,LVEDP和血浆TXA2浓度升高(P＜0.05).与AMI组比较,P组LVSP、±dp/dtmax、血浆PGI2浓度和PGI2/TXA2升高,LVEDP和血浆TXA2浓度降低(P＜0.05).AMI组和P组心肌梗死体积比较差异无统计学意义(P＞0.05).结论 帕瑞昔布钠可改善急性心肌梗死大鼠左心室功能,其机制与调节PGI2/TXA2相对平衡有关.

Effect of parecoxib on cardiac function after acute myocardial infarction in rats

Objective To investigate the effect of parecoxib on cardiac function after acute myocardial infarction (AMI) in rats. Methods Twenty-four adult male SD rats, weighing 230-250 g, were randomly divided into 3 groups ( n = 8 each): group Ⅰ sham operation (group S), group Ⅱ AMI and group Ⅲ parecoxib (group P). Myocardial infarction was induced by ligation of left anterior descending branch (LAD) of coronary artery in group Ⅱ and Ⅲ . In group S, LAD and cervical sympathetic trunk were exposed but not ligated and transected.Group P received intrperitoneal parecoxib 8 mg/kg once a day for 3 days 24 h after ligation of LAD, while group AMI received normal saline instead. At 4th day after ligation LAD, the left ventricular systolic pressure ( LVSP),left ventricular end-diastolic pressure (LVEDP) and ± dp/dtmax were measured and recorded. Blood samples were taken from common carotid artery to determine the plasma concentrations of TXA2 and PGI2 and PGI2/TXA2 was calculated. Then the animals were sacrificed and hearts removed. Myocardial infarct size of left venicle was calculated. Results Compared with group S, LVSP, ± dp/dtmax, plasma concentrations of PGI2 and PGI2/TXA2 were significantly decreased, while LVEDP and plasma concentrations of TXA2 increased in group AMI and P( P ＜0.05). Compared with group AMI, LVSP, ± dp/dtmax, plasma concentrations of PGI2 and PGI2/TXA2 were significantly decreased, while LVEDP and plasma concentrations of TXA2 increased in group P ( P ＜ 0.05). There was no significant difference in myocardial infarct size between group AMI and P (P ＞ 0.05). Conclusion Parecoxib can improve cardiac function after AMI in rats and the mechanism is related to regulation of the balance of PGI2/TXA2.