Effects of Overtraining on the Ultrastructure Changes and Three-Dimensional Construction of Rats´ Cerebral Microvessels

The aim of the study is to reconstruct the three-dimensional (3-D) structure of cerebral microvessels in the overtraining rats´ model, and observe the changes of ultrastructure and the 3-D structure of cerebral microvessels. In this study, 24 SD male rats were randomly divided into two groups, namely control rats (Group C) and overtraining rats (Group O), the rats in group O were burdened progressively when given five weeks of swimming exercises. At the end of the fifth week, all the rats were decapitated immediately and gained cerebral cortex after they swam exhaustively. The samples were investigated for ultrastructure analysis and also scanned by Laser Scanning Confocal Microscope (LSCM) for reconstructing cerebral microvascular 3-D structure. The results showed that there were obvious changes including swollen mitochondria with concomitant expanded endoplasmic reticulum, and a few of fingerlike bulges occurred in the basement membrane of the endothelial cells which extend to the microvascular cavity. In addition, the cerebral microvascular number, area and density increased in group O. The present study indicated that he dysfunction of cerebral neuron may be a reasons that cause the exercise-induced central fatigue. The study may provide the new methods and new evidence for further research in the mechanism of exercise-induced central fatigue.