高乌甲素对烧伤大鼠的镇痛作用及机制初步研究  

Aanalgesic effect and mechanism of lappaconitine on burned rats

作　　者：张兰英[1] 张福安[1] 肖智[2] 魏在荣[3] 

机构地区：[1]遵义医学院基础医学院临床医学系 [2]遵义医学院基础医学院生理学教研室 [3]遵义医学院附属医院烧伤整形外科

出　　处：《中华损伤与修复杂志（电子版）》2012年第1期21-25,共5页Chinese Journal of Injury Repair and Wound Healing(Electronic Edition)

基　　金：遵义医学院大学生创新性实验计划项目[院发(2011)2716]

摘　　要：目的探讨腹腔注射高乌甲素(lappaconitine,LA)对烧伤大鼠热痛阈和P2X3受体在中脑导水管周围灰质表达的影响。方法 SD大鼠100只随机分为正常组、单纯烧伤组、烧伤LA1组、烧伤LA2组和正常LA组。观察大鼠Ⅱ度烧伤以及LA治疗后行为学和热痛阈变化;免疫组织化学法检测大鼠在Ⅱ度烧伤前后以及经LA治疗后,P2X3受体在中脑导水管周围灰质的表达变化。结果大鼠Ⅱ度烧伤后,单纯烧伤组热痛阈逐渐下降,烧伤后48h达到最低值(10.88±2.35)s,与正常组(25.67±1.49)s比较差异有统计学意义(P<0.001)伴P2X3受体在中脑导水管周围灰质的表达上调(542.50±100.44)个/mm2,与正常组(440.80±88.58)个/mm2比较差异有统计学意义(P<0.01)。在烧伤后各时间点,烧伤LA1组、烧伤LA2组与单纯烧伤组比较,热痛阈升高;免疫组化检测提示:烧伤后48h,烧伤LA1组、烧伤LA2组P2X3受体在中脑导水管周围灰质的表达上调,与单纯烧伤组比较,差异有统计学意义(P<0.01),且LA镇痛效果和P2X3受体表达水平与LA的剂量成正相关。结论腹腔注射高乌甲素可促进Ⅱ度烧伤大鼠热痛阈的提高以及上调P2X3受体在中脑导水管周围灰质中表达,从而增强机体内源性镇痛系统的作用,缓解大鼠Ⅱ度烧伤后疼痛反应。Objective To explore the effects of intraperitoneally administrated lappaconitine （LA）, an active principle isolated from Chinese herbal medicine, on thermal withdrawal latency （TWL） and the P2X3 receptor expression in the midbrain periaqueductal gray （PAG） on burned rats. Methods Rats were randomly divided into 5 groups： normal group, burn group, burn plus LA1 group, burn plus LA2 group and normal plus LA group. The effect of LA on pain threshold was behaviorally characterized by TWL testing. The expression alteration of P2X3 receptor in the PAG was assessed by immunohistochemical analysis. Results In burn group, the TWL was significantly decreased compared with the normal group after burn injury （ P 〈 0.01 ）. In burn plus LA1 group and burn plus LA2 group , the TWLs were increased compared with the bum group （P 〈 0.01 ）. Burn plus LA2 group also has a higher value of TWL than burn plus LA1 group （P 〈0.01 ）. The expression of P2X3 receptor in the PAG was denser in burn group （542.50 ± 100.44） / mm2 than normal group（440.80 ±88.58） /mm2 on 48 h post-bum （P 〈0.01 ）. The administration of LA on burned rats induced a significantly up-regulated P2X3 receptor expression in the PAG and this effect is positively related to the dose of LA （P 〈 0.01 ）. Conclusion LA produces a lasting analgesic effect on burn pain and increases expression of P2X3 receptors in the PAG. The present study addressed the involvement of purinergic signaling system in LA analgesia on burn pain in rat burn model, as could deepen the understanding of the mechanism of LA analgesia and provide a rational basis for enhancing LA analgesic effect by potentiating the function of purinergic signaling system at supraspinal level.

关 键 词：烧伤 疼痛 痛阈 水管周灰质 受体 P2X3 

分 类 号：R644[医药卫生—外科学]