巴曲酶对兔全脑缺血-再灌注损伤的保护作用

Neuroprotective effect of Batroxobin in rabbits with global ischemia-reperfusion

目的研究巴曲酶对兔全脑缺血-再灌注损伤的治疗作用,探讨减轻心肺复苏(CPR)后脑再灌注损伤的有效措施。方法采用根据Pittsburg方法改良的开胸致颤模型,将32只新西兰兔随机分为3组,假手术组不致颤,常规复苏组、巴曲酶组致颤6分钟后复苏,巴曲酶组于复苏开始时给予巴曲酶静脉推注(0.3Bu/kg),复苏后4小时、12小时分别取血测血清NO浓度,第二次取血后终止实验,取脑皮质行电镜、光镜观察。结果CPR4小时常规复苏组、巴曲酶组血清NO浓度显著增高,巴曲酶组较常规复苏组明显降低(P<0.05);12小时常规复苏组进一步升高(P<0.05),但巴曲酶组与4小时相比相差不显著。皮质组织学检查发现常规复苏组神经细胞水肿疏松,部分神经元固缩;线粒体、粗面内质网水肿;胞核浓缩、深染,严重者出现细胞凋亡;毛细血管内可见微血栓形成。而巴曲酶组细胞肿胀、线粒体及粗面内质网肿胀较前者减轻,固缩神经元明显减少;未见毛细血管内微血栓形成。结论巴曲酶对兔全脑缺血-再灌注损伤具有保护作用,而降低NO浓度可能是其作用机理之一。

Objective To study the neuroproteetive effect of Batroxobin in rabbits with global ischemia-reperfusion and explode the potential treatment to ameliorate cerebral reperfusion injury caused by cardiac arrest. Methods Modified Pittsburg＇s model of mechanical ventricular fibrillation was used. Thirty-two rabbits were randomly divided into 3 groups： 8 in sham operated group, 12 in conventional resuscitation group and 12 in Batroxobin group. Sham operated group was discharged on the chest wall,which did not cause ventricular fibrillation. Conventional resuscitation group and Batroxobin group were exposed to 6 min of cardiac arrest（CA） induced by ventricular fibrillation, then resuscitation began. A dosage of 0.3Bu/kg of Batroxobin was given to Batroxobin group at the beginning of resuscitation. Blood samples were collected 4h, 12h after CPR for evaluation of NO concentration in serum. The experiment terminated after the second collection and cerebral cortex was observed by both light microscope and electronic microscope. Results Nitric oxide concentration in serum of both conventional resuscitation group and Batroxobin group increased when compared with sham 4h after CPR（P〈0.05）,and the concentration of conventional resuscitation group was higher than that of Batroxobin group （P〈0.05）. Significant different was found in the three groups （P〈0.05）. 12h after CPR, nitric oxide concentration of conventional resuscitation group was higher than 4h after CPR （P〈0.05）, but it didn＇t happened in Batroxobin group. Severity of ischemic injury of cortex was in the same turn. Microthromb can be found in some capillaries in conventional resuscitation group. Conclusion＇ Batroxobin may protect the rabbit＇s brain from ischemia-reperfusion injury, where one of the mechanisms may be decreasing NO concentration.