心肌声学造影评价大鼠心脏移植急性排斥反应模型心肌血流灌注的动态变化

Dynamic myocardial perfusion in acute rejection models of rats following heart transplantation with myocardial contrast echocardiography

目的评价心肌声学造影在检测大鼠心脏移植急性排斥反应心肌灌注变化中的价值。方法采用BrownNorway大鼠23只为同种异体移植供体[雄性,12～15周,体质量(143±23)g],Lewis大鼠53只为同种异体移植受体、同系移植供体及受体[雄性,12～15周,体质量(158±19)g]建立大鼠心脏移植模型(同种异体移植18只,同系移植12只),按移植后第2、4、6天分为3组(每组同种异体移植6只、同系移植4只),分别行心肌声学造影,自动拟合曲线,比较不同组间A、β及A×β值差异及同组内同系移植与同种异体移植大鼠间差异。结果成功建立大鼠心脏移植模型(同种异体移植18只,同系移植12只)。同种异体移植大鼠于术后第6天A值(15.87±4.20)、β值(0.320±0.019)、A×β值(4.974±1.355)显著降低(P<0.05,P<0.01),同系移植大鼠术后第2天A值(21.71±0.017)、β值(0.365±0.013)、A×β值(7.908±0.374)低于第4、6天(P<0.05)。在同种异体与同系比较中,A与β值于术后第6天均有差异(P<0.05),而A×β值则于术后第4天出现差异(P<0.05),到第6天差异更加显著(P<0.01)。结论心肌声学造影可反映大鼠心脏移植后缺血再灌注及急性排斥反应发展过程中心肌灌注逐渐下降的变化特点,对于急性排斥反应的诊断与监测具有应用价值,A×β值为较敏感指标。

Objective To assess the value of myocardial contrast echocardiography （ MCE ） for the myocardial perfusion of acute rejection in rats following heart transplantation. Methods Twenty-three male Brown Norway rats aged 12 -15 weeks with a BMI of 143 ± 23 g were used as allograft donors, and 53 male Lewis rats aged 12 - 15 weeks with a BMI of 158 ± 19 g were used as allograft recipients （ n = 23 ） , isograft donors （n = 15 ） and recipients （n = 15 ） in this study. Rat heart transplantation models were established by transplanting allograft in 23 rats and by transplanting isograft in 15 rats. Thirty established transplanted rats were divided into 3 groups on days 2, 4 and 6 with 6 allografts and 4 isografts in each, and then underwent MCE. Automatic fitting curve was plotted. A, 13 and A x 13 values were compared among 3 groups and between allograft and isograft transplantation groups. Results The rat heart transplantation models were successfully established in 18 allograft rats and in 12 isograft rats. The A, 13 and A x 13 values were significantly lower in allograft transplantation group P 〈O. O5,P 〈O. O1） and in on day 6 after transplantation （ 15.87± 4.20, 0. 320 ± 0. 019, 4. 974± 1. 355, isograft transplantation group on day 2 than on days 4 and 6 after transplantation （21.71±0.017, 0. 365 ±0.013, 7. 908 ±0. 374, P 〈0.05）. A significant difference was found in the A and 13 values between allograft and isograft transplantation groups on day 6 after transplantation （P 〈 0.05 ） and the A x 13 value was significantly different on day 4, especially on day 6, after transplantation （ P 〈 0.05, P 〈 0. 01 ）. Conclusion MCE can show the gradually decreasing myocardial perfusion characteristics of ischemia/ reperfusion and acute reiection in rats followin heart transplantation, and can thus be used in the diaznosis andmonitoring of acute rejection, in which the A value is a rather sensitive index.