实验性脑血管痉挛中PKC活性表达及其意义

The Role of Protein-kinase C in the Development of Vasospasm Caused by Experimental Subarachnoid Hemorrhage in Dogs

目的 :探讨蛋白激酶 C(PKC)在实验性蛛网膜下腔出血所致脑血管痉挛发生发展过程中的作用及意义。方法 :采用成年犬枕大池二次注血法建立脑血管痉挛动物模型 ,通过非放射性同位素标记蛋白激酶测定法动态测定犬脑基底动脉平滑肌细胞 PKC活性。结果 :动态脑血管造影显示 ,实验组 day4组和 day7组基底动脉口径分别为正常对照组基底动脉口径的 (73.8± 3.4) %和 (5 1.1± 2 .1) % ,与对照组比较差异显著 (P <0 .0 1) ;day4和day7组均有膜 PKC活性升高、胞浆 PKC活性相应降低 ,与对照组比较 day4组无显著差异 (P >0 .0 5 ) ,day7组差异显著 (P <0 .0 1) ,day 4和 day 7组之间差异显著 (P <0 .0 1)。结论 :脑血管痉挛过程中 PKC被持续激活 ,并在脑血管痉挛病理发展过程中起关键作用。

Objective:To verify the role of protein kinase C(PKC) in the development of vasospasm caused by subarachnoid hemorrhage (SAH) in dogs.Methods:The double hemorrhage canine models were established by injecting 3.0 ml/kg of autologous blood into the cisterna magna on day 1 and day 4 respectively, and PKC activity was measured in canine basilar artery with a nonradioisotopic protein kinase assay kit in various groups. Results:The vessel diameters in both day 4 and day 7 group decreased significantly compared with that of the control group after induction of SAH(P<0.01); membrane PKC activity increased with a reciprocal decrease in cytosolic PKC activity in the two groups. The change is significant(P<0.01) in day 7 group but not in day 4 group(P>0.05). Both vessel diameter and PKC activity differ significantly between day 4 and day 7 group (P<0.01).Conclusion:PKC activity was constantly activated under the condition of SAH. PKC as a calcium sensitive phospholipid dependent protein kinase might play a key role in the development of vasospasm after SAH.