Effects of Treadmill Running during Different Lifetime on Neurogenesis in the Hippocampal Dentate Gyrus of SD Rats

In order to explore the effect of treadmill running during different lifetime on neuro- genesis in the hippocampal dentate gyrus of SD rats,male Sprague-Dawley rats(5 weeks of age)were used for the experiment,and divided into the control group,exercise-1,exercise-2, and exercise-3 groups.The three exercise groups were forced to run on treadmill based on the exercise plan.The neurogenesis in the dentate gyrus and cingulate gyrus were investigated via intraperitoneal injection of 5-bromo-2'-deoxyuridine(BrdU)and immunohistochemisty.The result shows that the number of new ceils in dentate gyrus of hippocampus in the exercise-1 group,which were made to run during young age,was the most in the four groups(P0.01).The number of new cells in dentate gyrus of hippocampus in the exercise-2 group, which were made to run for 37 days,was less than that of the control group(P0.01).The number of new cells in dentate gyrus of hippocampus in the exercise-3 group,which were made to run during the later period,was near to that of the control group.It concludes that treadmill running during young age can enhance neurogenesis in the dentate gyrus of SD rats later and excessive running is not helpful for neurogenesis in the dentate gyrus of SD rats.