Figure 4. Chronic unpredictable mild stress (CUMS) induced decreased mRNA expression of neurotrophic factors and its receptors in the retina. The mRNA expressions of brain-derived neurotrophic factor (BDNF), tyrosine protein kinase receptor B (TrkB), nerve growth factor (NGF), tyrosine protein kinase receptor A (TrkA), and ciliary neurotrophic factor (CNTF) in the retina decreased at the end of 5 weeks of CUMS exposure compared with normal controls. Data are presented as mean ± standard error of the mean (SEM), n = 5–6.*p<0.05. **p<0.01.