D-丝氨酸在七氟醚多次麻醉诱发新生小鼠神经细胞凋亡中的作用：GSK-3β的关系

Role of D-serine in nerve cell apoptosis induced by multiple exposures to sevoflurane anesthesia in newborn mice： the relationship with GSK-3β

目的 评价D-丝氨酸在七氟醚多次麻醉诱发新生小鼠神经细胞凋亡中的作用及其与糖原合成酶激酶-3β（GSK-3β）的关系.方法 健康雄性C57B/L6小鼠30只,6日龄,体重3.5-4.5g,采用随机数字表法分为3组（n=10）：对照组（C组）、七氟醚多次麻醉组（S组）和D-丝氨酸组（D组）.S组和D组于出生第6、7和8天每天10：00吸入30％氧气＋3％七氟醚2h,并于吸入前30 min时分别腹腔注射生理盐水0.1 ml或D-丝氨酸500 mg/kg;C组于每天10：00吸入30％氧气,并于吸入前30 min时腹腔注射生理盐水0.1 ml.于出生第8天吸入氧气或七氟醚结束后处死小鼠,取脑组织,采用Western blot法检测磷酸化GSK-3β（pGSK-3β）和活化的caspase-3的表达水平.结果 与C组比较,S组脑组织pGSK-3β表达下调,活化的easpase-3表达上调（P〈0.05）,D组上述指标差异无统计学意义（P〉0.05）;与S组比较,D组脑组织pGSK-3β表达上调,活化的caspase-3表达下调（P〈0.05）.结论 D-丝氨酸可通过抑制GSK-3β的激活,参与七氟醚多次麻醉诱发新生小鼠神经细胞凋亡.

Objective To evaluate the role of D-serine in nerve cell apoptosis induced by multiple exposures to sevoflurane anesthesia in newborn mice and its relationship with glycogen synthase kinase-3 beta （GSK-3β）.Methods Thirty healthy male C57B/L6 mice,aged 6 days,weighing 3.5-4.5 g,were divided into 3 groups （n =10 each） using a random number table：control group （group C）,multiple exposures to sevoflurane anesthesia group （group S） and D-serine group （group D）.On postnatal days 6,7 and 8,3% sevoflurane in 30% oxygen was inhaled for 2 h starting from 10：00 daily,and normal saline 0.1 ml and D-serine 500 mg/kg were intraperitoneally injected at 30 min before inhalation in S and D groups,respectively.In group C,30% oxygen was inhaled for 2 h starting from 10：00 daily,and normal saline 0.1 ml was intraperitoneally injected at 30 min before inhalation.The animals were sacrificed after the end of oxygen or sevoflurane inhalation on postnatal day 8,and the brains were removed for determination of the expression of phosphorylated GSK-3β （pGSK-3β） and activated caspase-3 in brain tissues by Western blot.Results Compared with group C,the expression of pGSK-3β in brain tissues was significantly down-regulated,and the expression of activated caspase-3 in brain tissues was up-regulated in group S （P〈 0.05）,and no significant change was found in the parameters mentioned above in group D （P〉0.05）.Compared with group S,the expression of pGSK-3β in brain tissues was significantly up-regulated,and the expression of activated caspase-3 in brain tissues was down-regulated in group D （P〈0.05）.Conclusion D-serine is involved in the nerve cell apoptosis induced by multiple exposures to sevoflurane anesthesia through inhibiting the activation of GSK-3β in newborn mice.