关键词: HIE模型, 缺氧缺血, 脑损伤, 病理变化, 急性期

Abstract: Objective　The pathological changes in brain tissue during the acute phase were analyzed by establishing a neonatal SD rat HIE model.Methods　CT imaging data of 54 newborns with severe HIE in our hospital were collected to analyze the location of brain injury. The HIE animal models of 24 newborn 7-day-old SD rats were established, and their brain tissues were collected at 1, 3, 6, and 9 hours after modeling. Ischemic area and pathology of thalamus, cortex, and hippocampal tissue, and changes of  cellular oxidative stress, apoptosis and necrosis were analyzed through TTC, HE, Nissl staining, and flow cytometry.Results　The thalamus of children with severe HIE were most affected. The morphology of neurons in the right thalamus LDDM, LDVL, cortex S1BF, M2, RSA, and hippocampus CA1 regions had changed, and the staining had gradually become lighter and the number of cells had gradually decreased after 1-3 hours of modeling. During 3-6 h, the staining in each region had become lighter and lighter, and the changes of cell morphology and quantity were significant. At the same time, ischemic necrosis of cortical S1BF region had gradually appeared. During 6-9 h, The changes in tissue morphology and cell numbers of each regions were more pronounced, and ROS began to increase. Conclusion　3-6 hours after the establishment of HIE models is equivalent to the first stage of clinical HIE pathological and physiological development, and 6-9 hours is equivalent to the second stage, and after 9 hours is equivalent to the third stage. Therefore, before 3 hours is the best time window for intervention and treatment of neonatal HIE rat models.

Key words: HIE model, hypoxia ischemia, brain injury, pathological changes, acute phase