Effect of enriched environment on learning,memory and hippocampal expression of BDNF and TrkB in rats with vascular dementia

Objective To investigate the effect of enriched environment(EE) on learning, memory and hippocampal expression of brain derived neurotrophic factor(BDNF) and tyrosine kinase B(Trk B) in rats with vascular dementia(VD). Methods Male SD rats were randomly divided into sham, EE and VD groups. VD models were established by permanent ligation of bilateral common carotid arteries. On 7, 14 and 30 days postoperation, Morris water maze and immunohistochemistry were used to detect the learning and memory, and expression of BDNF and Trk B in CA1 region of the hippocampus, respectively. Results The escape latency was higher but the number of across platform and BDNF and Trk B positive cells was lower in the VD group than those in the sham group on 7, 14 and 30 days(P0.01). However, compared with the VD group, the escape latency was decreased, while the number of across platform and BDNF and Trk B positive cells was increased in the EE group on 14 and 30 days(P0.01 or 0.05). Conclusion EE can improve the learning and memory in VD rats, which might be related to the upregulation of BDNF and Trk B expression.