水蛭提取液对实验性脑内血肿周围组织tPA、PAI-1的影响

Effects of hirudo extract liquor on tPA and PAI-1 in experimental intracerebral peri-hematoma tissues of Wistar rats

目的探讨水蛭提取液对实验性脑内血肿周围组织组织型纤溶酶原激活物(tPA)、纤溶酶原激活剂抑制物1(PAI-1)的影响。方法采用成组设计的随机对照研究。用定量胶原酶注入大鼠尾状核来建立脑出血模型,酶联免疫吸附法、发色府物法检测血肿周围脑组织生化指标(tPA、PAI-1含量与活性)变化,RT-PCR法观察鼠脑血肿周围脑组织tPA与PAI-1 mRNA的表达,免疫组化法观察鼠脑血肿周围脑组织tPA蛋白的表达。结果水蛭提取液治疗组较生理盐水对照组能增加血肿周围脑组织tPA含量、提高其活性,促进血肿周围脑组织tPA mRNA表达,增强tPA免疫表达,而不影响PAI-1含量与活性或mRNA表达。结论水蛭提取液促进实验性脑内血肿吸收的机制可能为通过对tPA的转录、翻译及合成蛋白的加工修饰来激活内源性纤溶系统,对PAI-1无影响。

Objective To study the effect ofhirudo extract liquor （HEL） on activities of tissue-type plasminogen activator （tPA） and plasminogen activator inhibitor-1 （PAI-1）, as well as the levels of tPA and PAI-1 in experimental intracerebral peri-hematoma tissues of Wistar rats. Methods The experimental models of Wistar rats with intracerebral hemorrhage （ICH） were established by steoreotaxically injecting quantitative collagenase （0.7 U collagenase Ⅶ） into their left caudate nuclei. The rats were separated randomly into two groups： HEL test group and NS control group. In the study, biochemical indexes including activitives and levels of tPA and PAI-1 in PHT and variation of semi-quantification of tPA, PAI-1 mRNA levels by RT-PCR in PHT, were determined respectively. Activities of tPA and PAl were measured by colorimetric assay. Contents of tPA and PAI-1 were respectively determined by specific ELISA. Expression of tPA protein in PHT was investigated by immunohistochemistry. Results （1）The tPA amount, activity and its mRNA expression in PHT were increased on the 3^rd day and the 6^th day after experimental ICH, showing a trend of dose-dependence in the experiment. However, PAI-1 amount, PAl relative activity and PAI-1 mRNA expression were not obviously depressed. （2）HEL could increase tPA amount, activity and its mRNA expression, posing little influence on PAI-1 level, PAl relative activity or PAI-1 mRNA expression in PHT of rats after ICH. Conclusion （1） The increase of local fibrinolysis activity in PHT could eccelarate the absorption of hematoma during the acute phase of experimental ICH. （2）The pharmaceutical mechanisms of HEL on cerebral hematoma in rats after ICH may be related to activation of local endogenous fibrinolytic system mainly through upregulating tPA amount, activity and mRNA expression, enhancing the expression of tPA protein immunoreactivity and exerting no effect on PAI-1.