大鼠岛叶电点燃致痫模型建立后神经肽Ghrelin的表达变化

Expression of neuropeptides ghrelin in insular electrical kindled rats＇ model

目的 通过构建大鼠岛叶电点燃致痫模型,观察神经肽Ghrelin的表达变化特征,探讨其表达意义.方法 将雄性SD大鼠随机分为空白对照组、假手术组和点燃组.点燃组又分为点燃后1、3、7、10、14d5个亚组.立体定向下将电极植入大鼠岛叶,建立致痫模型,观察大鼠行为学变化,监测大鼠脑电情况;采用酶联免疫吸附试验（ELISA）法和免疫组织化学、实时荧光定量聚合酶链反应（PCR）分别检测血清和下丘脑中Ghrelin的表达水平.结果 从行为学、电生理多方面证实成功建立大鼠岛叶电点燃致痫模型;与空白对照组和假手术组比较,ELISA检测点燃后各亚组血清中Ghrelin浓度的表达水平均降低[1 d：（4.46±0.15） μg/L,3 d：（3.92±0.07）μg/L,7 d：（2.16±0.18） μg/L,10 d：（3.04 ±0.85） μg/L,14 d：（3.28 ±0.09）μg/L],差异有统计学意义（P＜0.05）,免疫组织化学和荧光定量PCR测定点燃后各亚组中大鼠下丘脑内Ghrelin的表达明显减少,差异有统计学意义（P＜0.05）.结论 证实岛叶本身具备致痫潜能,岛叶电点燃构建的癫痫模型提供了稳定的动物实验平台;癫痫发作后Ghrelin水平明显降低;准确检测血清Ghrelin水平,可以反映下丘脑中相应神经肽的变化趋势.

Objective To set up the insular electrical kindled rats＇ model and to observe expression level of neuropeptides ghrelin.To explore its significance at last.Methods The male SD rats were divided randomly into the blank group,the sham-operated group and kindled group.The latter were divided to 5 subgroups of 1,3,7,10 and 14 d after the rats had been seizure.By stereotactic operation,electrodes were placed in the rats insular and set up the model.Changes of behaviors and ECoG of the rats were observed simultaneously.Enzyme linked immunosorbent assay （ELISA）,immunohistochemistry and realtime polymerase chain reaction （PCR） were used to detect the expressions of Ghrelin in the serum and hypothalamus of the epilepsy rats.Results From the behavior and ECoG in epileptic rats confirmed that the rats of electrical kindled to insular can be successfully established experimental animal models.Compared to the blank group,the sham-operated group,all kindled groups of the seizure rats had a decreased expression of ghrelin through ELISA detect in the rats＇ serum [（1 d：（4.46 ± 0.15） μg/L,3 d：（3.92 ± 0.07） μg/L,7 d：（2.16 ±0.18） μg/L,10 d：（3.04 ±0.85） μg/L,14 d （3.28 ±0.09） μg/L].Immunohistochemistry and real-time PCR detect in the rats＇ hypothalamus （P 〈 0.05）.Conclusion The insular has the seizure potency.An accurate detection of serum expression level of ghrlin may reflect the fluctuation trend of neuropeptides in hypothalamus.