异丙酚减轻氯胺酮麻醉对幼年大鼠海马神经元和认知功能的损害（英文）

Propofol alleviates damage to hippocampal neurons and cognitive function of infant rats receiving ketamine anesthesia

目的探讨异丙酚与氯胺酮复合麻醉对幼鼠发育中大脑认知功能的影响。方法 SD幼年大鼠被随机分为生理盐水组(NS组),氯胺酮组(K组);异丙酚组(P组),异丙酚+氯胺酮组(P+K组),每组20只,均腹腔注射相应药物1 ml,维持麻醉6 h。麻醉结束后各组幼鼠随机分为相同数量的A、B两部分,每部分10只。A部分于麻醉结束后取出幼鼠海马组织制作石蜡切片,进行海马CA1区神经元凋亡和蛋白质Bcl-2/Bax表达的分析;B部分于麻醉结束后3周行Morris水迷宫测试。结果 K组凋亡率较NS组明显增加(P<0.05);P+K组凋亡率较P组明显上升(P<0.05),但与K组相比,凋亡率明显减少(P<0.05)。P+K组Bcl-2/Bax蛋白相对表达明显低于P组,但明显高于K组(P<0.01)。Morris水迷宫结果显示K组学习记忆功能明显差于NS组(P<0.05);P组及P+K组学习记忆功能优于K组(P<0.05)。结论异丙酚复合氯胺酮麻醉,可明显减轻氯胺酮所致的幼年大鼠海马神经元的凋亡和大鼠远期认知功能的损害,异丙酚上调Bcl-2基因表达可能是其作用机制之一。

【Objective】To evaluate the effect of propofol on the damage to hippocampal neurons and cognitive function induced by ketamine anesthesia in infant rats.【Methods】Eighty infant SD rats were randomized into normal saline group（group NS）, ketamine group（group K）, propofol group（group P）, propofol plus ketamine group（group P＋K）. At 6 h after the initial injection, the rats in each group were subdivided into two units： unit A and unit B. In the unit A, the rats were sacrificed and the hippocampus tissues were harvested for paraffin sections, followed by determination of neuron apoptosis and Bcl-2/Bax protein expression. In the unit B, the cognitive function of the rats was de-tected using the Morris water maze 3 weeks after anesthesia.【Results】The apoptosis index（AI） of CA1 neurons in hippocampus in the group K was significantly higher than that in the group NS（P〈0.05）. The AI in the group P＋K was significantly higher than that in the group P（P〈0.05）, but significantly lower than that in the group K（P〈0.05）. The expression ratio of Bcl-2/Bax protein in hippocampus CA1 neurons in the group P ＋K was significantly lower than that in the group P, but increased significantly compared to those in the group K（P〈0.01）. The learning and memory function in the group K was poorer than that in the group NS（P〈0.05）, whereas those in the groups P and P＋K were better than that in the group K（P〈0.05）.【Conclusions】Propofol alleviates the damage to hippocampal neurons and cognitive function of infant rats receiving ketamine anesthesia. Bcl-2 protein upregulation induced by propofol might play an important role in the protective effects.