摘要
目的观察完全弗氏佐剂所致慢性炎性疼痛对新生大鼠空间学习记忆功能发育的影响及其机制。方法10窝新生SD大鼠,每窝6只,随机分为疼痛组和对照组,在大鼠出生后第2天,疼痛组大鼠左足底皮下注射完全弗氏佐剂20μl,对照组注射等量生理盐水。分别在大鼠出生后第10天和第21天,两组每窝各取1只幼鼠处死后取海马组织,采用逆转录聚合酶链反应技术测定海马前脑啡肽mRNA的表达。幼鼠出生后第21天开始,两组每窝各取1只幼鼠进行Morris水迷宫实验。结果隐藏平台实验中,在出生后第21天和第24天疼痛组大鼠潜伏期较对照组延长(P<0.05),在空间探索实验中,疼痛组大鼠穿过平台所在象限游泳时间与总游泳时间、路径与总路径的比例均低于对照组(P<0.05),两组大鼠可视平台实验中潜伏期比较差异无统计学意义(P>0.05);在出生后第10天和第21天,疼痛组大鼠海马前脑啡肽mRNA表达均低于对照组(P<0.05)。结论慢性炎性疼痛可影响新生大鼠海马学习记忆功能的发育,海马前脑啡肽表达的下调可能是其中的机制之一。
Objective To investigate the effects of chronic inflammatory pain induced by injection of complete Freund＇ s adjuvant （CFA） into the plantar surface of hindpaw on the development of learning and memory and proenkephalin mRNA expression in hippocampus of neonatal rats. Methods sixty neonatal SD rats （6 rats from each of 10 litters） were randomly divided into control and chronic pain group （ n = 30; 3 rats from each of the 10 litters）. In chronic pain group CFA 20/.d was injected subcutaneously into plantar surface of left hindpaw on the 2nd day after birth whereas in control group normal saline 20 μl was injected instead of CFA. Ten animals （ 1 rat from each of the 10 litters） in each group were killed on the 10th and 21st day after birth respectively. Hippocampi were removed for determination of proenkephalin mRNA expression by RT-PCR. Ten animals （ 1 rat from each of the 10 litters） in each group underwent Morris water maze test 3 times a day for 8 days starting from the 21st day after birth. Results The mean latent period before the rats found the hidden platform was significantly longer in chronic pain group than in control group. When the platform was removed the swimming time and distance of the rats in chronic pain group were significantly shorter than those in control group. There was no significant difference in the latent period before the rats found the visible platform between the two groups. The proenkephalin mRNA expression in hippocampus on the 10th and 21st day after birth was significantly lower in chronic pain group than in control group （ P 〈 0.05）. Conclusion Chronic inflammatory pain could impair the development of learning and memory ability of newborn rats. The decrease in proenkephalin mRNA in hippocampus partly explains the underlying mechanism.
出处
《中华麻醉学杂志》
CAS
CSCD
北大核心
2005年第8期601-603,共3页
Chinese Journal of Anesthesiology
