The Second Affiliated Hospital of Xinxiang Medical University, Henan Key Laboratory of Biological Psychiatry, Xinxiang, PR China.
Mol Med Rep. 2012 Oct;6(4):889-93. doi: 10.3892/mmr.2012.1009. Epub 2012 Jul 26.
The aim of this study was to investigate the correlation between brain-derived neurotrophic factor (BDNF) expression and cognitive impairment in post‑stroke depression (PSD) rats and to explore the mechanism(s) involved in the process of cognitive impairment. A rat model of focal cerebral ischemia was established by occluding the middle cerebral artery (MCA). Rats were subjected to isolation-housing combined with chronic unexpected mild stress (CUMS) to establish a PSD rat model. The learning and memory abilities of the PSD rat model were evaluated by passive avoidance tests. Real‑time PCR and immunohistochemical methods were used to detect changes in BDNF mRNA and protein expression in the hippocampus. Passive avoidance defects were revealed in the PSD and depression groups. Passive avoidance defects were more evident in the PSD group compared with the depression group and the difference was statistically significant (P<0.05). BDNF expression in the hippocampus was significantly lower in the PSD and depression groups compared with that in the normal control group (P<0.01). No significant difference in BDNF expression was identified between the normal control and stroke groups (P>0.05) or between the PSD and the depression groups (P>0.05). The decrease in BDNF expression in the hippocampus of PSD rats may aggravate cognitive impairment, however, the degree of cognitive impairment cannot be reflected by the expression levels of BDNF in the hippocampus.
本研究旨在探讨脑源性神经营养因子（BDNF）表达与脑卒中后抑郁（PSD）大鼠认知障碍的相关性，并探讨认知障碍过程中涉及的机制。通过阻断大脑中动脉（MCA）建立局灶性脑缺血大鼠模型。采用隔离饲养联合慢性不可预知性轻度应激（CUMS）建立 PSD 大鼠模型。通过被动回避试验评估 PSD 大鼠模型的学习记忆能力。采用实时 PCR 和免疫组织化学方法检测海马区 BDNF mRNA 和蛋白表达的变化。PSD 和抑郁组均出现被动回避缺陷。与抑郁组相比，PSD 组的被动回避缺陷更为明显，差异有统计学意义（P<0.05）。与正常对照组相比，PSD 和抑郁组大鼠海马区 BDNF 表达显著降低（P<0.01）。正常对照组与卒中组（P>0.05）或 PSD 组与抑郁组（P>0.05）之间 BDNF 表达无显著差异。PSD 大鼠海马区 BDNF 表达减少可能加重认知障碍，但海马区 BDNF 表达水平不能反映认知障碍的程度。
