炎性痛-吗啡耐受大鼠DRG辣椒素受体表达的变化及电针对吗啡耐受的影响  

Changes in expression of vanilioid receptor subtype 1 in dorsal root ganglion and effect of electroacupuncture on morphine tolerance in rats with inflammatory pain and morphine tolerance

作　　者：郑宇欣[1] 于泳浩[1] 王国林[1] 张素品[1] 

机构地区：[1]天津医科大学总医院麻醉科,300052

出　　处：《中华麻醉学杂志》2010年第9期1054-1057,共4页Chinese Journal of Anesthesiology

基　　金：高等学校博士学科点专项科研基金（20060062002）;天津市卫生局科技基金（2010KZ107）;天津医科大学科学基金（2007KY29）

摘　　要：目的 探讨炎性痛-吗啡耐受大鼠背根神经节（DRG）辣椒素受体（VR1）表达的变化及电针对吗啡耐受的影响.方法 鞘内置管成功的雄性SD大鼠30只,采用左后足踝关节腔注射完全弗氏佐剂（CFA）50μl的方法制备炎性痛模型.随机分为6组（n=5）：A组于注射CFA后第4天,鞘内注射生理盐水10μl,2次/d,连续7 d;B组不制备炎性痛模型,鞘内注射吗啡10μg/kg（10μl）,2次/d,连续7 d;C组于注射CFA后第4天,鞘内注射吗啡10μg/kg（10μl）;D组于注射CFA后第4天,鞘内注射吗啡10μg/kg（10μ1）,2次/d,连续7 d;E组鞘内给药方法同D组,同时每天首次给药后,电针大鼠阳陵泉和足三里,强度2 mA,频率2 Hz,时间30 min;F组：电针频率为15 Hz,余同E组.于炎性痛模型制备前、鞘内注药前1 d、鞘内注药第1～7天时测定大鼠后肢热缩足潜伏期（PWL）.吗啡第7天末次给药后采用Western blot方法测定DRG总蛋白及细胞膜蛋白VR1的表达.结果 各组炎性痛模型制备前PWL比较差异无统计学意义（P＞0.05）.B组和D组发生吗啡耐受,E组和F组未发生吗啡耐受.D组DRG总蛋白及细胞膜蛋白VR1表达水平最高,E组VR1表达水平低于F组（P＜0.05）.结论 DRG VR1表达上调参与了大鼠吗啡镇痛耐受的形成;电针刺激可抑制吗啡镇痛耐受的形成,该作用与下调DRG VR1的表达有关.Objective To investigate the changes in expression of vanilloid receptor subtype 1 （VR1） in dorsal root ganglion （DRG） and effect of electroacupuncture （EA）on morphine tolerance in rats with inflammatory pain （IP） and morphine tolerance. Methods Thirty 8 month old male SD rats in which intrathecal （IT） catheters were successfully implanted without complication were randomly divided into 6 groups （ n = 5 each）： group A IP ＋ normal saline （NS） 10 μl IT twice a day × 7 days;group B intact rats ＋ morphine 10 μg/kg（10 μl ）IT twice a day × 7 days;group C IP ＋ morphine 10 μg/kg（10 μl） IT once;group DIP ＋ morphine 10μg/kg（10 μl） IT twice a day × 7 days;group E and F IP ＋ EA （frequency 2/15 Hz） ＋ morphine 10μg/kg（10 μl） IT twice a day × 7 days. IP was induced by injecting complete Freund＇s adjuvant （CFA） into the anlle joint of the left hindlimb. IT morphine or NS was started on the 4th day after induction of IP. EA of Yanglingquan and Zusanli lasting 30 min was performed once a day after first IT administration of morphine for 7 days. Paw withdrawal latency （PWL） to a thermal nociceptive stimulus was measured before induction of IP （baseline）, at 1 day before and 1-7days of consecutive IT administration. The animals were sacrificed after last PWL measurement. The DRGs of the lumbar segment （L4-6） were removed for determination of VR1 expression in total and membrane protein using Western blot analysis. Results There was no significant difference in the baseline PWL measured before induction of IP among the 6 groups. Morphine tolerance developed in group B and D but did not develop in group E and F.The expression of VR1 in total and membrane protein of DRG was highest in group D and was significantly lower in group E than in group F. Conclusion VR1 in DRG is involved in the development of morphine tolerance. EA can inhibit morphine tolerance by down-regulating the expression of VR1.

关 键 词：药物耐受性 吗啡 炎症 电针 TRPV阳离子通道 

分 类 号：R245.97[医药卫生—针灸推拿学]