Chronic mild stress induces memory deficit with asymmetrical damages in the hippocampus in rats [Sıçanlarda kronik ilımlı stres hipokampusta asimetrik hasarlar ve bellek bozukluklarına neden olur]

Background: major depressive disorder (mdd) is associated with deficits in memory which is often caused by hippocampal damages. left-right asymmetry of human brain has been understood for a century. chronic mild stress (cms) protocol is widely used to evoke depressive-like behaviors in laboratory rats. few studies have been done to examine the relation between depression and left-right asymmetry hippocampal damages. this paper aimed to investigate the impacts of cms on both sides of the hippocampus,learning and memory.methods: body weight and sucrose preference and a modified open-field test was performed to check the depressive-like behaviors of cms model. learning and memory,apoptosis rates and chemiluminescence density of the hippocampus were determined.results: compared with normal control,cms group showed less weight gain with age,decreased sucrose intake and reduced open-field exploration indicative of depression; cms had a negative effect on performance in the step-through test,reflecting a deficit in learning memory; cms group had a greater increase in the apoptosis rates and chemiluminescence density in the left hippocampus,but with no significant change in the right one.conclusions: these findings suggest that cms may cause the asymmetrical damages in the hippocampus which induce a deficit in learning and memory in rats. © 2014,ege university press. all rights reserved.