基底神经节出血对新生大鼠脑区多巴胺转运体表达的影响

目的:探讨新生大鼠基底神经节出血的病理变化及其对大鼠脑内多巴胺转运体(DAT)表达的影响。方法:将48只出生后10d(P10)SD幼鼠,雌雄不拘,随机分为脑出血(CH)组、假手术(SH)组及正常对照(NC)组,每组各16只。利用立体定位仪向SD大鼠脑尾状核注入自体血25μl,建立脑出血模型,假手术组只将微量注射泵针头刺入大鼠左侧尾状核,不注血,其他处理同脑出血组,正常对照组不做任何处理,正常饲养。术后24 h,从各组大鼠中各随机选择1只经麻醉、断头取脑、常规固定等步骤,冠状位切开大脑,行形态学观察。术后第17天各组大鼠经麻醉、处死、快速取脑并于4%多聚甲醛溶液中固定24 h,行H-E染色观察脑组织病理学变化,免疫组织化学显色测定基底神经节区DAT蛋白表达。结果:术后第17天脑出血组大鼠基底神经节可见血肿吸收空腔形成,同时见少许淋巴细胞浸润,空腔周围出现少许胶质瘢痕形成;假手术组与正常对照组无炎性细胞浸润,细胞分布正常。脑出血组大鼠基底神经节脑区内DAT免疫反应阳性产物增多,与假手术组及正常对照组比较,差异具有统计学意义,而假手术组与正常对照组比较差异无统计学意义。结论:新生大鼠基底神经节局灶性出血所致的损伤,可导致脑内DAT表达水平增高,这可能与儿童早期脑损伤相关的远期发育行为障碍相关。

Effect of basal ganglia hemorrhage on dopamine transporter expression of neonatal rat`s brain

Objective: To investigate the pathological changes after basal ganglia hemorrhage and the effects of basal ganglia hemorrhage on the expression of dopamine transporter(DAT) in neonatal rats.Methods: Forty-eight neonatal rats(10 days after birth) were equally and randomly divided into cerebral hemorrhage(CH) group,sham operation(SH) group and normal control(NC) group.Stereotaxic apparatus was used to inject autologous blood into caudate nucleus of SD rats so as to establish basal ganglia hemorrhage model.Rats in the SH group were injected through the syringe needle with no blood and rats in the NC group were fed normally without any treatment.One rat was selected from each group randomly 24h after operation and then was anesthetized,decapitated,fixed and the brain was cut from the coronal plane to observe the morphological changes of rat brain.On the 17th day after operation,each rat was anesthetized,decapitated,fixed in 4% paraformaldehyde solution for 24h and then the pathological changes of rat brain were investigated by hematoxylin-eosin and DAT protein expression in the basal ganglia was detected by immunohistochemistry.Results: On the 17th day after operation,H-E staining showed that there were cavities after absorption of hematoma in the basal ganglia of rats in the CH group.There were some lymphocytes and a few glial scar formations around the cavity.SH and NC groups showed no hematoma,no inflammatory cells,and cell distribution was normal.Immunohistochemistry showed the integrated optical density(IOD) of DAT in the basal ganglia of rats was bigger in the CH group than the SH and NC groups and the difference was statistically significant.There was no significant difference between the SH group and the NC group.Conclusion: Damage caused by focal hemorrhage in the basal ganglia of neonatal rats can increase the expression of DAT,which might be related to the long-term developmental-behavioral disorders caused by early brain damage of children.