Swimming Training Modifies Stress-induced Changes in the Hippocampal Morphology and Spatial Memory in Rats

Abstract

This study assessed the effect of swimming training on morphology (Glial fibrillary acidic protein (GFAP), dark cells and thickness of CA1 and DG) of the hippocampus and spatial memory performance in young male rats exposed to chronic stress. Adult male wistar rats were randomly assigned to five groups: swimming training (ST); exposure to chronic mild stress (CS); exposure to chronic mild stress followed by swimming training (CS + ST); exposure to chronic mild stress followed by a recovery period (CS + recovery); control group with no exercise or stress intervention. Spatial memory was measured by Morris Water Maze (MWM). Results: The lowest GFAP and number of dark cells, the highest thickness of CA1, DG, and spatial memory performance were observed in the ST group. In the CS + ST group, swimming training reduced GFAP and the number of dark cells, increased thickness of CA1 and DG, and memory performance, compared to control and CS + Recovery. In the CS group, GFAP and the number of dark cells were highest and thickness of CA1 and DG were lowest among the study groups. In the CS + Recovery group, GFAP, and the number of dark cells were lower, compared to the CS group. Conclusion: swimming training could attenuate astrogliosis and the number of dark cells in both stressed and non-stressed rats and its effect on non-stressed rats was more prominent than in stressed rats. Among young male rates, swimming training could improve stress-induced spatial memory performance and hippocampal morphology.