运动训练对实验性脑出血大鼠血肿周围组织细胞凋亡及海马CA1区超微结构的影响

The effect of exercise on apoptosis of neuronal cells surrounding brain tissue and hippocampus histological changes in rats with intracranial hematoma

目的观察运动训练后血肿周围组织细胞凋亡情况和组织学改变，以及海马CAI区超微结构方面的表现，以研究运动对出血性脑损伤细胞凋亡的影响及其改善神经功能的机制。方法88只SD大鼠被随机分为3组，实验组（40只，出血并运动）、对照组（40只，出血不运动）和假手术组（8只，无出血，不运动），前两组又分为术后24h、7d、14d、21d、28d等5个时相点，每个时相点取5只用于TUNEL检测及光镜观察，3只用于电镜观察。结果实验组和对照组血肿周围、大脑皮质、海马等脑组织在ICH后24h出现典型的细胞凋亡特征（电镜及TUNEL染色），实验组不同时相点凋亡细胞数明显较对照组和假手术组减少（P〈0．05），而血管增生却较对照组和假手术组更明显（光镜）。结论运动训练可以通过抑制脑出血后血肿周围及海马区的神经细胞凋亡，增加血管再生，从而改善神经功能。

Objective To investigate the effects of cage-running exercise （EX） on apoptosis of neuronal cells surrounding the hematoma and histological changes of hippocampus in rats with experimental intracranial hematoma （ICH）. Methods A total of 120 male SD rats weighted 270 to 300 g were randomly divided into a trial group （ ICH with EX, n = 40） , a control group （ ICH with no EX, n = 40） and a sham operated group （no ICH and EX, n = 40）. The brains of the rats were removed at 24 h, 7,14,21 and 28 days after ICH. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-bioti in situ nick end-labeling （TUNEL） was used to detect deoxyribonucleic acid （DNA） fragmentation. Light and electron microscopy were used to observe histological changes of the hippocampus and the tissues surrounding the hematoma. Results （ 1 ） Under light microscope, typical histological changes of ICH were seen at 24 hours after operation in the trial and control groups. After exercise, a lot of new capillary were seen in perimeter of hematoma and hippocampus of rats, in contrast, the control group and sham group had little. （2） Under electron microscope, shrunken neuron and glial cell with pre-apoptotic signs of intensely stained cytoplasm and abnormally dense nucleus, swollen mitochondrials, blood vessel, Golgi apparatus and rough endplasmic reticulum were seen in the control group. In trial group rats, the main alterations were dim pre-and post-synaptic membranes. （3） TUNEL-positive cells appeared in the periphery of the hematoma and hippocampus. The number of TUNEL-positive cells in trial group was less than that in control group, with a significant difference existed between the two groups （ P 〈 0.05 ）. Conclusion Exercise training （ cage-running ） can suppress the number of apoptotic cells, and increase regeneration of capillary after ICH in rats.