脑缺氧缺血增加新生大鼠海马区TLR4的表达

Objective: In this study, we investigated the expression of Toll-like receptor 4 (TLR4) in the hippocampus in neonatal rat following hypoxic-ischemic brain injury. This study will provide new idea for intervention of neonatal brain injury. Methods: Thirty-six 7-day-old SD rats were divided into hypoxia-ischemia group and sham group randomly. The hypoxia-ischemia brain injury models were made by ligaturing left common carotid artery and then breathing 8%O2+92%N2 for 2 hours. The rats of sham group were only interfered with left common carotid artery dissection, without ligation and hypoxia. The brain tissues were collected at the 3d, 7d and 14d respectively. There are 6 rats in every group at each time point. The expression of TLR4 were detected by immunohistochemical staining and western blot. Results: Immunohistochemical staining showed that TLR4 positive cells were increased in hippocampal CA1 region, CA2 and CA3 region in rats with hypoxic-ischemic brain injury, compared with the control group, especially in CA1 region. There is a significant difference between the two groups at the 3d and 7d time points (P <0.01). Western blot showed the same results with immunohistochemistry. Conclusion: Expression of TLR4 is increased in hippocampus in neonatal rats following hypoxic-ischemic brain injury, which suggesting that TLR4 involved in hypoxic-ischemic brain injury.