Changes of brain-derived neurotrophic factors in rats with generalized anxiety disorder before and after treatment.

Abstract

The aim of the current study was to investigate the association between brain-derived neurotrophic factor (BDNF) and generalized anxiety disorder (GAD). A total of sixty male adult Wistar rats with similar body weight and age were randomly divided into 3 groups the blank control group (CON, n=20), the saline control group (SAL, n=20), and the combined medication group (Deanxit +fluoxetine, DF, n=20), then rats in group SAL and group DF were prepared for model of anxiety disorder for 14 days. The body weight, center-retention time (CRT) and square-crossover number per unit time (SCN) were compared during modeling to define the anxiety of rats on day 1, day 7 and day 14; the BDNF mRNA in brain were detected by RT-PCR and the protein of BDNF in brain were detected by immunohistochemistry before and after intervention. The body weight, CRT and SCN in group SAL and DF after modeling were decreased with time compared with CON (p<0.05). The rats were taken euthanasia after 14 days, the BDNF mRNA showed significant decrease in SAL group (0.58±0.07) compared with group CON (2.87±0.23), while in DF group (1.76±0.21), the BDNF mRNA were higher than SAL group but lower than CON (p<0.05); the BDNF positive cells in group CON was highest (90%), then was group DF (75%) and group SAL was the lowest (35%). The changes in the indexes of the rats among different groups before and after modeling showed that after modeling, the body weights of the rats in group SAL and group DF were lower than group CON, the CRT decreased, and the SCN increased. The differences were statistically significant (p < 0.05), indicating that the combined medication (Qilixin + fluoxetine) can improve anxiety symptoms (body weight, CRT, and SCN). Anti-anxiety drugs (Deanxit+fluoxetine) can improve anxiety symptoms of rats and increase the expressions of BDNF mRNA and protein in rat brain cells. Anxiolytic drugs (Deanxit+fluoxetine) may achieve the treatment of anxiety disorders through improving the 5-HT nervous system and the expressions of BDNF mRNA and protein. BDNF can be used as a biochemical indicator for the diagnosis and efficacy evaluation of GAD.