Study on pathogenesis of hypoxic-ischemic on brain damage

Wistar rats of 7-old were randomly divided into tow groups : hypoxic-ischemic(HI) group,and control group.The tow groups rats were made dead at 6,24,72 and 96 hour after hypoxia-ischemic by cutting head and the brain tissues were separately taken.Radioimmunoassay,transmission electron microscope technique,pyronin and methyl green(PMG) staining and hematoxylin and eosin(HE) staining were used to meature dynamic changes of the content of tumor necrosis factor-α(TNF-α),interleukin-1 β(IL-1 β) and the number of apoptosis cell,and to evaluated the changes of histopathological morphology of left brain tissue.The content of water was meatured in right brain tissue.The results were as follows: The content of TNF-α and IL-1β increased significantly in brain tissue of hypoxic-ischemic newborn rats as compared with those of control groups.The result showed that cytokine participated brain damages of hypoxic-ischemic encephalopathy in newborn rat.The number of apoptosis cells were significantly higher than those of control group in brain tissue of hypoxic-ischemic newborn rats.The result certified that the brain damages of hypoxic-ischemic encephalopathy had close relationship with cell apoptosis in newborn rat.The content of water were higher than those of control group in right brain tissue of hypoxic-ischemic newborn rats.The result showed that local cerebral hypoxia and ischemia caused brain damages not only in local cerebra but also in whole cerebra.