ABSTRACT
Objective To investigate the changes and the significance of the number of nerve cells and the expression of the postsynaptic density tyrosine kinase(Fyn) in the hippocampus of the rat whose spatial learning and memory function was enhanced by chronic multiple stress. Methods Thirty-nine adult rats were randomly divided into three groups: multiple stressed,single stressed and control group.Rats in the multiple stressed group were irregularly and alternatively exposed to the situation of vertical revolve,sleep expropriate,restraint(6h/d),and night illumination for 6 weeks,to preparate chronic multiple stressed model.Rats in the single stressed group were exposed to restraint only for 6 weeks,6h/d.After that,the performance of spatial learning and memory of all rats was measured using Morris water maze.Nerve cells in different subfields of the hippocampus were observed using Cresyl violet method and counted regardless of size or shape.The expression of Fyn protein and the level of Fyn mRNA in the hippocampus of rats were detected by immunohistochemical method and RT-PCR technique respectively. Results Compared with control group,the performance of spatial learning and memory of rats was increased in multiple stressed group and decreased in single stressed group((P
ABSTRACT
Objective To study the neurogenesis of the dentate gyrus(DG) and the expression of the doublecortin(DCX) in the hippocampus of the rat whose spatial learning and memory function was enhanced by chronic multiple stress. Methods Adult male Wistar rats were randomly divided into two groups: multiple stressed group and control group.Rats in the multiple stressed group were irregularly and alternatively exposed to the chronic multiple stress for 6 weeks.After that,all rats were tested for the performance of spatial learning and memory in Morris water maze.The number of newborn neurons in the DG was counted by using immunocytochemical method.The expression of the DCX protein and the level of DCX mRNA in the hippocampus of rats were measured by using Western blotting and RT-PCR technique,respectively. Results The results showed that: 1.Compared with the ones of the control group,the multiple stressed rats had a significantly shorter latent period to search the platform in Morris water maze(P