Dopamin促进出血性卒中大鼠恢复的作用机制研究

The mechanism of action of dopamine promoting rehabilitation to the rat of intracerebral hemorrhage

目的应用多巴胺(dopamine)对实验性脑出血大鼠进行腹腔注射,研究dopamine对出血性卒中的神经保护作用机制。方法 SD雄性大鼠60只,体质量300±20g,造脑出血模成功后随机分为dopamine治疗组、生理盐水(NS)对照组(n=30),同一条件下饲养。每天进行神经功能评分,不同亚组按相应时间点取材。分别测定出血周围脑组织胶质纤维酸性蛋白(GFAP)和脑源性神经营养因子(BDNF)的免疫组化评分。取脾组织制作匀浆,反转录聚合酶链式反应(RT-PCR),测定转录调节家族中叉头翼状双螺旋家族的一个独特的成员Foxp3与β-actin的相对密度值,表示CD4+、CD25+、T细胞的活性。结果 dopamine组大鼠与NS组在对应时间点进行神经功能评分,显示前者高于后者差异有统计学意义(P<0.05)。GFAP和BDNF在实验大鼠脑组织中的表达,dopamine组均高于相应对照组差异有统计学意义(P<0.01)。Foxp3mRNA在dopamine组的大鼠脾脏中的表达与相应的对照组比较,差异有统计学意义(P<0.01)。结论 dopamine能上调实验性脑出血大鼠脑内GFAP和BDNF蛋白表达水平,促进神经症状的好转。CD4+、CD25+、调节性T细胞对中枢神经系统损伤的恢复有抑制作用;dopamine可下调CD4+、CD25+、调节性T细胞对D4+Th1细胞的抑制作用,促进出血性卒中大鼠脑损伤的恢复。

Ob jective To explore the neuroprotective mechanism of dopamine on intracerebral hemorrhage （ICH）.Methods The male adult Sprague-Dawley rats （ experimental ICH rats ）.Weighing 300 ±20g, were randomly divided into dopamin group （ 30 rats ） and normal sodium （ NS ） group （ 30 rats ） .Each group had five subgroups, including 1d（one day after ICH, 6 rats）, 3d（three days after ICH,6 rats） 7d（7 days after ICH,6 cats）, 14d（14 days after ICH, 6 cats）, 21d （21 days afer ICH, 6 cats）.We appraised Longa’ s behavioral score everyday. Different subgroups were drawn materials according to the corresponding time . The CFAP and BDNF immunohistochemical score in perihematoma tissue was measured separately .Using RT-PCR to detect the mRNA expression of Foxp3 in spleen.The ratio between Foxp3 andβ-actin represented the activity of CD4＋,CD25＋, T cell. Results The longa ’ s behavioral score in dopamin group was higher than that in NS group , the difference was significantly different（p〈0.05）.dopamin group had higher GFAP and BDNF immunonis to chemical score than NS group.The difference was significantly different （p〈0.01）.In contrast with NS group, the Foxp3 mRNA expression in spleen was lower ,the difference was significantly different （ p〈0.01） .Conclusion Dopamin could upregulate the level of GFAP and BDNF expression in the brain tissue of ICH rats and improve symptoms of neurological impairment . Immunoprotective mechanism of dopamine：down-regulating the inhibiting effect of the CD 4＋, CD25 ＋, regulatory T cell against CD 4＋Thl cell.