Effects of the brain-derived neurotrophic factor on the post-stroke depressive behavior

Abstract

Objective To investigate the change of rats behaviors after injecting exogenous brain-derived growth factor(BDNF)to hippocampus of the post-stroke depression(PSD)rat. Methods After open-field test, removed the rats whose cross and vertical scores below 30 and above 120 points were removed, then 24 were selected to meet the group conditions, and were randomly divided into four groups:PSD, PSD injection of saline group, PSD injection high or low dose of BDNF groups, each 6 rats. The focal cerebral ischemia model was set up by blocking the middle cerebral artery(MCA), and then the model rats were separately raised and put into chronic unpredictable mild stress to induce the PSD model. In the third day, through stereotaxic instrument to inject BDNF into rats hippocampus, and assessed behavioral changes. Results Begin with the fourteenth day of the stress, the sugar consumption ratio, cross and vertical scores of the high-dose injection group(each was 72. 09±8. 78, 50. 33±12. 44, 12. 50±1. 52)were significantly higher than PSD group(each was 54. 76±9. 88, 31. 00±21. 73, 6. 17±6. 31), and has statistic difference(P＜0. 05 or P＜0. 01), low dose injection group compare with PSD group was no significant difference. Compared with the PSD, saline group in the entire process of both stress behavior was no significant difference. Conclusion Anhedonia and underactivity, the core symptoms in the PSD patients, can be found completely and persistently in the PSD group rats, which mean the PSD model is an ideal model for the PSD research. High-dose injection of BDNF group improved the symptoms of the lack of pleasure, exploration of the decline of the core symptoms of depression, suggesting that the BDNF has antidepressant effect, but precise molecular mechanisms required study. Key words: Cerebrovascular accident; Depressive disorder; Animal models; Brain-derived neurotrophic factor(BDNF)