蝮蛇毒蛋白C激活物对全脑缺血再灌注损伤大鼠血-脑屏障通透性的影响

Effect of Agkistrodon halys Pallas Venom protein C activator on permeability of blood-brain barrier in total cerebral ischemia-reperfusion injury rats

目的探讨蝮蛇毒蛋白C激活物(PCA)对全脑缺血再灌注损伤大鼠血-脑屏障通透性的影响和可能的机制。方法以关闭和重开放双侧颈总动脉和基底动脉来复制大鼠全脑缺血再灌注损伤模型。按照体重将SD大鼠随机分为5组:假手术组、模型组和低、中、高3个剂量实验组,每组10只。于造模前,低、中、高3个剂量实验组分别尾静脉注射PCA 1,3,6 mg·kg-1,假手术组和模型组给予等量0.9%NaCl。用试剂盒法检测大鼠血清肿瘤坏死因子α(TNF-α)含量;以酶联免疫吸附法检测大鼠脑组织细胞间黏附分子-1(ICAM-1);以伊文思蓝(EB)染色法观察大鼠血脑-屏障通透性。结果假手术组、模型组和低、中、高3个剂量实验组的TNF-α分别为(5.57±1.81),(25.37±1.96),(15.32±1.94),(13.31±1.79)和(10.47±1.71)pg·mg-1;这5组的ICAM-1分别为(56.80±5.96),(105.80±10.23),(76.60±5.56),(63.50±8.34)和(59.10±8.36) ng·mL-1;这5组的EB含量分别为(0.55±0.18),(1.61±0.19),(0.99±0.22),(0.72±0.18)和(0.54±0.09)μg·g-1。上述指标:模型组与假手术组比较,差异均有统计学意义(均P<0.01);低、中、高3个剂量实验组与模型组比较,差异均有统计学意义(均P<0.01),且随着PCA浓度的增加,效果越明显。结论 PCA可降低脑缺血再灌注损伤大鼠血-脑屏障的通透性,其机制可能与抑制炎症细胞因子、下调细胞黏附分子和减轻炎症反应有关。

Objective To investigate the effects of protein C activator(PCA)from Agkistrodon halys Pallas Venom on permeabiluty of blood-brain barrier in total cerebral ischemia-reperfusion injury rats and explore possible mechanisms. Methods Total cerebral ischemia-reperfusion injury model was established by closuring and re-opening the bilateral common carotid artery and basilar artery. Sprague-Dawley(SD) rats were randomly divided into five groups:sham-operation group,model group and experimental-L,-M,-H groups,ten rats in each group. experimental-L,-M,-H groups were given 1,3 and 6 mg·kg-1PCA respectively by the tail vein before copying model,while the sham operation group and the model group were given equal amount of 0.9%NaCl. Levels of tumor necrosis factor-α(TNF-α) in serum were detected by Kit. The content of intercellular adhersion molecule-1(ICAM-1) in brain tissue was detected by enzyme-linked immunosorbent assay. And the permeability of blood-brain barrier in rats was observed by Evans blue(EB) staining. Results Level of TNF-α in sham operation group,model group and low,middle,high dose experimental groups were(5. 57 ± 1. 81),(25. 37 ± 1. 96),(15. 32 ± 1. 94),(13. 31 ± 1. 79),(10. 47 ± 1. 71)pg·mg-1;the ICAM-1 level in the five groups were(56. 80 ± 5. 96),(105. 80 ± 10. 23),(76. 60 ± 5. 56),(63. 50 ± 8. 34),(59. 10 ± 8. 36) ng·mL-1;EB contents in the five groups were(0. 55 ± 0. 18),(1. 61 ± 0. 19),(0. 99 ± 0. 22),(0. 72 ± 0. 18),(0. 54 ± 0. 09) μg·g-1. Compared between model group and sham operation group,the difference of the factors were significant(all P < 0. 01);compared between experimental group and model group,the difference of the factors were significant(all P < 0. 01). And with the increase of PCA concentration,the effect was more obvious. Conclusion PCA can reduce the permeability of blood-brain barrier in rats with cerebral ischemia reperfusion injury. Its mechanism may be related to inhibiting inflammatory cytokines,down-regulating cell adhesion molecules,and reducing inflammatory response.