Effects of Voluntary Wheeling on Behavior Changes,Brain Neuropeptide Y and nNOS Expression within Central Amygdala in the Depressive Model Rats

Objetive:To explore the effects of the 4-week voluntary wheeling exercise on the depressive behavior and learning and memory, brain NPY and blood plasma Cort contents and nNOS expression within CeA in the depressive rats induced by Chronic Unpredictable Stress (CUMS) .Methods:45male SD rats were randomly allocated to 3groups, control group (C) , stress model group (SM) and stress exercise group (SE) .All rats except the C group are exposed CUMS and SE group rats receiced 4-week voluntary wheeling exercise at the same time.The behavioral changes were conducted by sucrose consumption test, forced swimming test and eight-arm radial maze test;brain NPY and blood plasma Cort contents were tested by radioimmunoassay;nNOS expression within CeA were detected by immunohistochemical.Results:Compared with the C group, sucrose water intaking and sucrose consumption ratio significantly decreased, immobility times prolonged in the forced swimming test, the time of completing 8-arms radial maze prolonged and WME, RME, TE significantly increased in the eight-arm radial maze test in the SM group.Adrenal gland index and the blood plasma Cort content significantly increased, the brain NPY content decreased and nNOS expression enhanced in SM group compared with the C group.Resultsshowed that voluntary wheeling exercise may significantly improve depressive behavior and learning and memory of the depressive rats;brain NPY content increased, adrenal gland index and blood plasma Cort content significantly decreased and nNOS expression weakened in the SM group compared with the SE group.Conclusion:The voluntary wheeling exercise may improve depressive behavior and enhance the learning and memory ability of the depressive rats, its mechanism might be that voluntary wheeling exercise increase brain NPY content, decrease blood plasma Cort cotent and reduce the nNOS expression within CeA.