大鼠脑震荡后大脑多巴胺D_1受体的动态表达观察

目的探讨大鼠脑震荡后不同时间大脑多巴胺D1受体在不同部位的表达变化。方法用金属单摆打击装置复制大鼠脑震荡模型,将56只大鼠随机分为脑震荡后1、2、4、8、16和24d 6个损伤组和1个正常对照组,每组8只。于大鼠脑震荡后不同时间取内侧隔核(MSN)、左右Broca斜角带垂直支(VDB)、丘脑网状带(RT)脑组织,用免疫组化染色(SP法)观察脑组织不同区域多巴胺受体(D1)表达情况,用图像分析系统进行定量分析。结果各组大鼠脑组织D1受体免疫组化阳性表达变化情况:在MNS区,脑震荡后1d细胞阳性表达开始减弱,到16d细胞阳性表达最弱,16～24d细胞阳性表达开始增强,但在24d仍比对照组的表达弱。在VDB区,脑震荡后1d细胞阳性表达开始减弱,2d细胞阳性表达最弱,脑震荡后2～24d细胞阳性表达开始增强,但在24d仍比对照组的表达弱。在RT区,脑震荡后1d细胞阳性表达开始减弱,4d细胞阳性表达最弱,4～24d细胞阳性表达开始增强,到24d与对照组表达接近。结论大鼠脑震荡后不同时间,脑组织多巴胺D1受体在MSN、VDB、RT不同区域的表达轻微下调,但下调差异无显著性意义。

The expression of D1 dopamine receptor in cerebral tissue after brain concussion in rats

Objective To explore the changes of expression of D1 dopamine receptor in the different parts of cerebral tissue in rats at the different time after brain concussion(BC).Methods The BC models of 48 SD rats were made by a simple metal pendulum and divided randomly into 6 groups of 1,2,4,8,16 and 24d.Other 8 rats were selected as a control group.The sections were cut from the medial septal nucleus(MSN),vertical of diagonal band(VDB) in nucleus of Broca and reticular thalamus(RT) and stained by immunohistochemical SP method.The expression of dopamine receptor(D1) of these different sites in every group was observed and analyzed quantitatively by the image analyzing system and compared with the control group at the same time.Results The D1 receptor expression in MSN area of all experiment groups reduced in the 1st day after BC and reached the lowest value in the 16th day,then it showed resume but still lower than the control group after 24 days.In VDB area,the expression showed similar to MSN in the 1st day after BC and reached the lowest value in the 2ed day,then it showed increasing but still lower than the control group after 24 days.In the RT area,however,the expression also reduced in the 1st day after BC and reached the lowest value in the 4th day,then it increased and get close to the control group after 24 days.Conclusion The expression of D1 dopamine receptor show slightly decrease in the RT,VDB and MSN of cerebral tissue at the different time after the brain concussion in rats,but the differences have no significance among these different neurons tissues.