瘦素对新生期惊厥大鼠行为学及Bcl2蛋白表达的影响

Effect of leptin on behavior and Bcl2 protein expression in rats with neonatal seizures

目的探讨瘦素对新生期惊厥大鼠的保护作用及其机制。方法20只6Et龄Spra—gue—Dawley（SD）大鼠随机分为四组：对照组（control组），瘦素组（1eptin组），惊厥组（RS组），惊厥＋瘦素组（RS＋leptin组），每组5只。在日龄6—12d时，Rs组和RS＋leptin组每日使用三氟乙醚反复诱导建立新生期惊厥模型；在日龄13～22d时，leptin组和Rs＋leptin组大鼠腹腔注射瘦素（2mg·kg^-1·d^-1）；日龄30d时检测各组大鼠的神经行为发育学指标（前肢悬吊实验和旷场实验）；日龄34d时取脑组织，Western blot检测大鼠大脑皮层Bcl2蛋白表达水平。结果（1）神经行为测试：前肢悬吊实验，RS组[（7．10±1．02）s]大鼠较control组[（15．95±6．11）s]前肢悬吊时间明显缩短（P〈0．05）；RS＋leptin组[（13．90±2．64）s]较RS组前肢悬吊时间明显延长（P〈0．05）；旷场实验，RS组[（119．80±28．83）格]大鼠较control组[（191．00±37．27）格]水平移动明显减少（P〈0．05）；RS＋leptin组[（164．20±26．46）格]较RS组水平移动增加，但差异无统计学意义；RS组大鼠较control组修饰次数和便粒明显增加（P〈0．05）；RS＋leptin组较RS组修饰次数和便粒明显减少（P〈0．05）；（2）免疫印迹结果：RS组（0．24±0．07）、leptin组（0．89±0．09）和RS＋leptin组（0．56±0．07）大鼠较control组（1．02±0．01）Bcl2表达均明显下降，差异具有统计学意义（P〈0．05）；RS＋leptin组和leptin组较Rs组Bcl2表达均明显升高（P〈0．05）。结论瘦素可以通过上调节Bcl2表达改善三氟乙醚诱导的新生期大鼠惊厥性脑损伤。

Objective To investigate the protective effects of leptin on neonatal seizure in rats by behavioral tests and Bc12 expression. Methods Twenty Sprague-Dawley （SD） rats were divided into four groups： control group ,leptin group,RS group and RS＋leptin group on postnatal day 6 （P6）, 5 rats in each group. From P6 to P12, repeated neonatal seizure model was induced by flurothyl in RS and RS＋leptin group rats. From P13 to P22, leptin （2 mg · kg^-1 · day^-1） was administered by intraperitoneal injection in leptin group and RS＋leptin group rats. Forelimb hanging test and open field test were implemented on P30.Bcl2 expression was detected by western blot on P34. Results （ 1 ） Neurobehavioral tests ： the time of forelimb suspension in RS group（ （7.10± 1.02） s）was significantly shorter （P〈0.05） than the control group（ （ 15.95±6.11 ）s） and the time of forelimb suspension in RS＋leptin group（ （13.90±2.64） s）was significant longer （P 〈0.05） than the RS group. In open field test, the number of horizontal movement in RS group（ 119.80±28.83） was significantly reduced （P〈0.05） than that in the control group（191.00±37.27） and the number of horizontal movement in RS＋leptin group （ 164.20±26.46 ） was increased than that in the RS group, but the difference was not significant. The number of modification and stool in RS group was significantly increased （P〈0.05） than that in the control group and the number of modification and stool in RS＋leptin group was significantly reduced （P〈0.05） than that in the RS group. （2）Western blot： the expression of Bcl2 in RS group （0.24±0.07） ,leptin group（0.89±0.09）and RS＋leptin group（0.56±0.07） was significantly decreased compared with control group （1.02±0.01） （P〈0.05）, and the expression of Bcl2 in RS ＋leptin group was significantly increased compared with RS group （P〈0.05）.Conclusion Leptin improves the brain injury induced by flurothyl on neonatal rats by Bcl2 signaling pathway.