孕早期氯胺酮麻醉对子代大鼠海马c-fos mRNA和c-jun mRNA表达的影响

Effect of ketamine anesthesia in early pregnancy on the c-fos mRNA and c-jun mRNA expression in offsprings of rats

目的 探讨孕早期氯胺酮麻醉对子代大鼠海马c-fos mRNA和c-jun mRNA表达的影响.方法 孕5～13 d的SD大鼠30只,体重250～300 g,随机分为2组（n=15）：对照组（C组）和氯胺酮组（K组）.K组经尾静脉注射氯胺酮20 mg/kg,随后以130 mg·kg-1·h-1的速率静脉输注2 h;C组以等量生理盐水替代氯胺酮.子代大鼠于出生后20和30 d时测定认知功能,取海马组织,测定c-fosmRNA和c-jun mRNA表达水平并观察超微结构.结果 与C组比较,K组子代大鼠出生后30 d时认知功能测定第2天逃避潜伏期延长（P＜0.05）,海马c-fos mRNA和c-jun mRNA的表达水平差异无统计学意义,出生后20 d上述指标差异无统计学意义（P＞0.05）.K组海马神经元发生损伤.结论 孕早期氯胺酮麻醉抑制子代大鼠认知功能的机制与海马神经元受损有关,但与海马c-fos mRNA和c-jun mRNA表达无关.

Objective To investigate the effect of ketamine anesthesia in the early pregnancy on the c-fos mRNA and c-jun mRNA expression in the offsprings of rats. Methods Thirty pregnant SD rats at 5-13 days of gestation were randomly divided into control group and ketamine group （n = 15 each）. Ketamine 20 mg/kg was injected intravenously through tail vein followed by 2 h infusion at a rate of 130 mg·kg-1 ·h-1 in ketmine group.While the equal volume of normal saline was given instead of ketamine in control group. The learning and memory function of the offsprings were tested by Morris water maze test on postnatal day 20 and 30. The hippocampal tissues were taken to detect the expression of c-fos mRNA and c-jun mRNA and to observe the ultrastructure. Results Compared with group C, the escape latency was significantly prolonged at 2 days during the test which was performed on postnatal day 30, but there was no significant difference in the expression of c-fos mRNA and c-jun mRNA on postnatal day 20 and 30 and in the indices mentioned above on postnatal day 20 in ketamine group （P 〉0.05）. The damage to hippocampal neurons happened in ketamine group. Conclusion The mechanism by which ketamine anesthesia in the early pregnancy inhibits the cognitive function of the offsprings is related to the hippocampal neuron damage, but not related to the expression of c-fos mRNA and c-jun mRNA in hippocampus.