脑梗死后抑郁大鼠脑内NK1受体表达变化的研究

Expression of NK1 receptor in brain tissue of rats with post-stroke depression

目的:探讨P物质受体NK1与脑梗死后抑郁的关系。方法:健康雌性SD大鼠48只,随机分成4组:抑郁组(MD组)、大脑中动脉皮质支闭塞组(MCAO组)、梗死后抑郁组(PSD组)和正常对照组,模型制做成功后第4周和8周利用敞箱试验评估大鼠抑郁程度,平衡木试验评估大鼠神经功能缺损程度,间接免疫荧光法检测脑内NK1受体的表达。结果:MCAO组和PSD组术后平衡木评分较同期正常对照组和MD组低,4周基本恢复正常。PSD、MD组各时点敞箱垂直活动、水平活动评分较同期MCAO、正常对照组低,8周较4周进一步降低,但PSD和MD组间比较差异无显著意义。PSD和MCAO组大鼠术侧皮质均见梗死灶,未累及基底节区,4周见中风囊形成,8周部分大鼠患侧侧脑室扩张;MD组和正常对照组未见脑梗死灶。梗死后4周,MD组和PSD组NK1表达阳性细胞平均灰度值均较同期MCAO组和正常对照组增高,8周进一步增高(P<0.05),但两组间差异没有显著性;MCAO组4周较对照组增高,8周基本正常。结论:NK1受体高表达与梗死后抑郁有关,可能参与梗死后抑郁的发生发展过程。

Objective： To identify the relationships between substance P-preferring receptor --NK1 receptor in brain tissue and post-stroke depression. Methods： Forty-eight healthy female Sprague-Dawley rats were randomly divided into four groups., major depression （MD） group, permanent middle cerebral artery occlusion（MCAO） group, post-stroke depression （PSD） group and normal control group. At the end of the 4th and 8th week, the neural funetion deficiency of rats was evaluated by Beam-walking test performance, the depression degree was evaluated by Open-Field method, and NK1 receptor expression in brain tissue was detected by indirect immunofluoroscence. Results：Scores evaluated by Beam-walking test in MCAO and PSI） groups were lower than those in control and MD groups after brain infarction, and then it was improved to the normal level at the 4th week. Scores evaluated by Open- Field method in PSD and MD groups were lower than the that in control and MCAO group, and it was much lower at 8th week, but its difference was not significant between the PSD and MD group. Isehemie infarction focus could be found in PSD and MCAO groups with normal basal ganglion, but it was not found in MD and control groups. ＂Stroke sac＂ was found in PSD and MCAO groups at 4th week with clear border, and/dilation of lateral ventricle was observed at 8th week in most of the rats. No infarct was seen in MD group and normal controis. The mean gray values of NK1 positive cell of the PSD （17.06±3.09） and the MD groups （16.72±2.04） at the end of 4th week were higher than that of MCAO （9. 46±1.70） and control group （5.55±0.85）, and it was even higher at the end of 8th week（31.08±2.28,28.24±4.93,5.66±0.78,5.50±1.03;P〉0.05）. But there was no difference between the PSD and the MD groups. The mean gray grades in MCAO group （9.46 ± 1.70） was higher than the control group at the end of 4th week, but it decreased to approach that of the control group at the end of 8th week （5.66±0.78）. Conclusion：The high expression of NK1 receptor and PSI） are related, and it might participate in the occurrence and development of PSD.