钾通道拮抗剂IBTX对大鼠低氧海马脑片的保护作用

Protective Effect of Potassium Channel Blocker IBTX on Ischemic Hippocapmpal Slice Culture and Mechanism

目的探讨钾通道拮抗剂IBTX对低氧损伤的海马脑片的保护作用及其机制。方法建立海马脑片低氧模型,将脑片分为空白对照组、低氧对照组、IBTX处理组。采用苏木精-伊红染色分别观察不同条件下培养的海马脑片CA1区的病理改变,计算海马区神经元的密度。应用末端脱氧核苷酸转移酶缺口标记(TUNEL)法及免疫组化Caspase-3染色法检测海马脑片CA1区神经元凋亡数目。结果空白对照组、低氧对照组、IBTX处理组海马脑片CA1区神经元密度分别为(114.67±5.72)(、51.22±4.71)、(72.25±2.55)个/mm,三者差异具有显著性意义(P<0.05或P<0.01)。高倍镜下低氧对照组海马脑片CA1区神经元凋亡细胞数显著高于IBTX处理组,两者差异具有显著性意义(P<0.05)。结论钾通道拮抗剂IBTX可以减轻低氧海马脑片的损伤,其作用机制可能与减少细胞凋亡有关。

Objective To explore the protective effect of potassium channel blocker IBTX on ischemic hippocapmpal slice culture and possible mechanisms. Methods The hypoxic model of hippocampal slices in SD rats was made. The hippocapmpal slices were divided into blank control group, hypoxic control group and IBTX-treated group. The pathological changes of the cultured hippocapmpal slices CA1 region were observed by HE staining. The density of neurons in hippocapmpal CA1 region was calculated. By using TUNEL method and Caspase-3 immunohistochemical staining, the number of apoptotic neurons in hippocapmpal CA1 region was detected. Results The density of neurons in hippocapmpal CA1 region in blank control group. hypoxic control group and IBTX-treated group was （114.67±5. 72）. （51.22± 1.71） and （72.25±2.55） /mm respectively. with the difference being significant among the three groups （P〈70.05）. Under a microscope, the number of apoptotic neurons in hippocampal CA1 region in hypoxic control group was significantly greater than in IBTX-treated group （P〈70.05）. Conclusion Potassium channel blocker IBTX can alleviate the injury of neurons in ischemic hippocampal slices by decreasing the apoptosis of neurons.