吗啡慢性处理及戒断后不同时期大鼠海马脑源性神经营养因子与trkB表达的变化

Expression of brain derived neurotrophic factor and trkB in hippocampus of chronic morphine addiction and withdrawal rat

目的：观察吗啡慢性处理及戒断后不同时期大鼠海马内脑源性神经营养因子（BDNF）与trkB的表达.方法： 实验组雄性成年SD大鼠以剂量递增的方法连续腹腔注射吗啡10d,每天2次.动物在戒断后0、1、7、14d和21d处死.对照组动物注射等量生理盐水,按同样方法处理.用免疫组织化学方法（ABC法）检测海马CA1区BDNF与trkB的表达.用Motic 3.2图像分析系统测定免疫阳性产物的平均光密度值.结果： 实验组BDNF免疫阳性产物的平均光密度值在戒断后0、1、7、14d和21d分别低于相应对照组,差异具有统计学意义,以戒断后14d下降最为明显.实验组trkB免疫阳性产物的平均光密度值在戒断后0、1、7、14d和21d分别也低于相应对照组,差异具有统计学意义.结论： 大鼠慢性吗啡成瘾及戒断后不同时间点BDNF与trkB在海马CA1区的表达明显下降,这种下降可能与大鼠吗啡成瘾及戒断后不同时期的行为学变化有关.

Objective： To observe the expression of BDNF and trkB in the hlppocampus of cnronm morphine addiction withdrawal rats. Mehhold： Male adult SD rats were intraperitoneally injected with morphine twice a day for consecutive 10 days in an ascending dosage schedule, and the control group rats were iniected with saline of the same volume. Then the rats were executed at 0 d, 1 d, 7 d, 14 d and 21 d after morphine withdrawal. BDNF and trkB expressions in CA1 area of hippocampus were detected by immunohistochemical technique （ABC method）, and the mean optic density of immunoreactive positive products were analyzed by Motic 3.2 image analysis system. Results： Compared with the control group, the expressions of BDNF in the hippocampal CA1 area of chronic morphine addiction and withdrawal group at withdrawal 0 d, 1 d, 7 d, 14 d and 21 d were reduced significantly （P 〈 0.01）, which was same in the expression of trkB with BDNF. Conclusion： These findings suggest that chronic morphine addiction and withdrawal can result in an expression decrease of BDNF and trkB in hippocampal CA1 area,which may contribute to the morphine addiction and withdrawal behavior.