The research in mechanism and effect of cognitive function by different intensity exercise in diabetes rat

Objective To investigate the possible effects of exercise intensity on the cognitive function in diabetic rats and explore the underlying mechanisms. Methods Forty Sprague-Dawley female rats were randomly divided into 4 groups (n=10 each): control,diabetic,diabetic and 1 h/d swimming,diabetic and exhausting exercise groups. Diabetes was induced using streptozotocin. Cognitive functions were evaluated three months later. Open-field test was used to test ability of activities and exploration behavior and Morris water maze (MWM) was used to examine the changes of the abilities of space search,learning and memory in rats,respectively. Collagen fiber proliferation in the hippocampus was analyzed by immunohistochemical staining with anti-fibronectin(Fn) antibody. Results Cognitive functions (the abilities of space search,learning and memory) were significantly decreased in diabetic rats compared with normal controls. 1 h/d swimming but not exhausting exercise significantly improved diabetes induced decline of cognitive functions. Similarly,diabetes lead to the significant increase of the Fn positive immunoreactivites in the hippocampus (P0.05). Swimming at 1 h/d significantly attenuated diabetes induced increase of Fn expression. Conclusions Proper exercise can improve the abilities of space search,learning and memory in diabetes rats probably through reducing Fn expression.