异喹啉磺酰类在凝血酶诱导的大鼠脑出血后脑损伤中的作用

Role of the isoquinoline sulfonamides on the brain damage following thrombin-induced cerebral hemorrhage in rats

目的探讨蛋白激酶C(PKC)抑制剂——异喹啉磺酰类(H-7)在凝血酶诱导的大鼠脑出血后脑损伤中的作用。方法取健康雄性SD大鼠54只,将其随机分为对照组、凝血酶组及H-7治疗组,每组18只。经大鼠右侧尾壳核注入凝血酶(10 U,50μl等渗盐水稀释),建立大鼠脑出血模型。在造模后即刻和24h,H-7治疗组腹腔注射H-7(1 mg/kg)各1次;对照组给予等量等渗盐水。造模后48 h,采用HE染色观察其组织病理学和炎性细胞浸润情况,伊文思蓝法检测血-脑屏障的通透性,干-湿重法测脑组织的含水量,TUNEL法观察损伤区细胞凋亡情况。结果①病理学观察显示,H-7可明显改善凝血酶造成的脑组织损伤。②对照组、凝血酶组、H-7治疗组右侧尾壳核周围脑组织炎性细胞计数分别为(0.8±0.7)、(16.5±1.0)、(10.0±1.4)个/高倍视野,细胞凋亡计数为(73±5)、(150±12)、(118±9)个/高倍视野,脑组织含水量为(77.5±1.1)、(83.2±0.4)、(78.8±0.9)%,伊文思蓝含量为(6.7±0.5)、(28.4±3.2)、(16.0±1.3)μg/g。凝血酶组与对照组和H-7治疗组比较,上述各指标差异均有统计学意义(P<0.05或P<0.01)。结论 H-7可以明显减轻凝血酶诱导的脑出血后的脑损伤。其可能通过抑制PKC而发挥神经保护作用。

Objective To investigate the role of the protein kinase C （ PKC ） inhibitor isoqninoline sulfonamides （H-7） on the brain damage following thrombin-induced cerebral hemorrhage in rats. Methods A total of 54 healthy male SD rats were randomly allocated into 3 groups： control, thrombin, and H-7 intervention groups （ n = 18 in each group）. Thrombin （ 10 U, dissolved in 50 μL isotonic saline） was injected into the right caudate nucleus to establish the rat model. Immediately after the modeling proce- dure and at 24 hours, H-7 （1 mg/kg） was injected intraperitoneally in the H-7 intervention group; equal amount of isotonic saline was injected intraperitoneally in the control group. Hematoxylin and Eosin （HE） staining was used to observe the histopathologica[ changes and inflammatory cell infiltration 48 hours after the modeling, the dye Evans blue assay was used to detect the blood-brain barrier （BBB） permeability, the dry-wet method was used to measure the brain water content, and TUNEL was used to observe the apoptosis in the injuried brain region. Results （1）Pathological observation showed that H-7 significantly improved brain injury induced by thrombin. （2）The inflammatory cell counts around the right caudate nucleus in the control, thrombin, and H-7 intervention groups were 0. 8 ± O. 7, 16.5 ±1.0, and 10.0 ± 1.4, respective- ly. The apoptosis cell counts were 73 ±5, 150±12, and 118 ±9. The brain water contents were 77.5 ±1.1, 83.2±0.4, and 78.8±0.9%. TheEBcontentswere6.7±0.5,28.4±3.2, and 16.0±1.3 μg/ g. When thrombin group compared with the control and H-7 intervention groups, there were significant differences among the above indices （P 〈 0.05 or P 〈 0.01 ）. Conclusion H-7 significantly reduces the brain injury following thrombin-indueed cerebral hemorrhage. It may play a neuroproteetive role by inhibi- ting the activation of PKC.