IGF-1在大鼠脑出血后脑组织中的表达及其对谷氨酸的影响

IGF-1 expression in the brain tissues and its effect on the expression of glutamate in rats after intracerebral hemorrhage

目的:研究胰岛素样生长因子-1(IGF-1)在实验性大鼠脑出血(ICH)后脑组织中的表达及其对谷氨酸(GLU)表达的影响。方法:应用立体定向技术,将自体未抗凝血注入大鼠尾状核头部以制备脑出血模型;将动物分为假手术组、实验组及干预组,分别在不同时间断头取脑以制作标本,连续切片分别作HE染色及IGF-1和GLU阳性细胞免疫组化染色。结果:脑出血后2h血肿周围脑组织IGF-124h达表达高峰,7d时恢复正常;GLU免疫组化染色阳性细胞于脑出血后2h开始出现,3d时达高峰,7d时仍有表达;给予外源性IGF-1后,GLU阳性细胞显著减少,与同时点实验组相比,差别有显著性。结论:脑出血后IGF-1的表达增加;IGF-1可抑制GLU的分泌,从而减轻脑出血后继发性脑损伤。

Objective：To investigate the expression of insulin-like growth factor-1 （IGF-1） in the brain tissues and the effect on the expression of glutamate in experimental rats after intracerebral hemorrhage. Methods：Unanticoagulated autologous blood was injected into the head of caudate nucleus of rats by stereotaxic method. After preparation of the experimental animal model, the rats were divided into groups of sham-operation, hemorrhage and intervention. Each rat was decapitated to obtain the brain tissues by serial section and immunohistochemistry method was used to detect the positive cells of IGF-1 and glutamate. Results：The IGF-1 positive cells were detected in brain tissues around the hematoma at 2 hour after intraeerebral hemorrhage, peaking at 2.4 hour, but revised to normal level on day 7. Glutamate positive cells were found at 2 hour with a peak on day 3 and yet were present in the brain tissues around the hematoma on the 7th day following the hemorrhage, but the glutamate positive ceils reduced significantly after intervention of exogenous IGF-1 as compared with the simultaneous experimental controls, which showed significant difference. Conclusion：The expression of IGF-1 increased after intracerebral hemorrhage suggests that IGF-1 could inhibit the expression of glutamate in the brain tissues, consequently preventing secondary injury of the brain after intracerebral hemorrhage.