延胡索总碱贴片安全性和对神经病理性疼痛大鼠镇痛作用研究

Safety and analgesic effect of total alkaloids of Corydalis yanhusuo patch on neuropathic pain rats

目的 探讨延胡索总碱贴片的安全性及其对神经病理性疼痛大鼠的镇痛作用及其机制。方法 (1)安全性实验:采用单次、多次给药的皮肤刺激性实验及皮肤过敏性实验,评价延胡索总碱贴片的安全性。(2)镇痛实验:取48只雄性SD大鼠,随机分为正常组、假手术组、模型组、布洛芬组、双氯芬酸钠贴片组及延胡索总碱贴片高、中、低剂量组,每组6只。除正常组和假手术组外,其余组大鼠采用坐骨神经慢性压迫损伤方法诱导神经病理性疼痛模型,术后第8天开始,布洛芬组灌胃给药,双氯芬酸钠贴片组及延胡索总碱贴片高、中、低剂量组分别给予双氯芬酸钠贴片及延胡索总碱贴片腹部贴敷,其余组腹部贴敷空白贴片,均每天1次,连续14 d。分别于术前及干预后1,3,7,10,14 d测定各组大鼠热缩足反射潜伏期;采用Western blot法检测各组大鼠干预结束后脊髓中Toll样受体4(TLR4)、核因子κB(NF-κB)、p38丝裂原活化蛋白激酶(p38MAPK)、信号传导和转录激活因子3(STAT3)蛋白表达情况。结果 (1)给予延胡索总碱贴片后,皮肤刺激反应评分均小于0.5分,致敏率为0,组织结构与正常皮肤无差异。(2)镇痛实验中,延胡索总碱贴片中、高剂量组干预后3 d和延胡索总碱贴片各剂量组干预后7,10,14 d患侧的热缩足反射潜伏期均明显长于同期模型组(P均<0.05);干预结束后,延胡索总碱贴片各剂量组大鼠脊髓中TLR4、NF-κB、p38MAPK蛋白相对表达量均明显低于模型组(P均<0.05), STAT3蛋白相对表达量均明显高于模型组(P均<0.05)。结论 延胡索总碱贴片安全性良好,可抑制慢性坐骨神经挤压损伤神经病理性疼痛大鼠痛觉敏感,其机制可能与抑制脊髓中TLR4、NF-κB、p38MAPK表达并上调STAT3的表达有关。

Objective It is to study the safety,analgesic effect and its mechanism of Corydalis yanhusuo total alkaloids transdermal patch(CTTP)in the rats with neuropathic pain.Methods①Safety experiments:skin irritation test and skin allergy test of single and multiple administration were used to evaluate the safety of CTTP.②Analgesia experiment:48 male SD rats were selected and randomly divided into normal group,sham-operated group,model group,ibuprofen group,diclofenac sodium patch group and CTTP high,medium and low dose groups,with 6 rats in each group.Except for the normal group and the sham-operated group,the rats in the remaining groups were induced with the chronic compression injury method of sciatic nerve to establish neuropathic pain models.Starting from the 8th postoperative day,the ibuprofen group was administered by gavage,the diclofenac sodium patch group and the CTTP high,medium and low dose groups were given diclofenac sodium patch and CTTP by abdominal patching,respectively,and the remaining groups were given blank patch by abdominal patching,all once a day,continuously treated for 14 days.The thermal shrinkage reflex latency of the rats in each group was detected before surgery and after treatment for 1,3,7,10,and 14 days.The expression of toll-like receptor 4(TLR4),nuclear factor kappa-B(NF-κB),p38 mitogen activated protein kinases(p38MAPK)and signal transducer and activator of transcription 3(STAT3)in spinal horn of the rats in each group was detected by Western blot at the end of experiment.Results①After treatment with CTTP,the skin irritation response scores were less than 0.5,the sensitization rate was 0,and the tissue structure was not different from that of normal skin.②In analgesic experiment,the thermal shrinkage reflex latency of the rats in the medium and high dose groups of CTTP after treatment for 3 days and each CTTP group after treatment for 7,10,14 days was significantly longer than that in the model group at the same period(all P<0.05).At the end of the intervention,the relative expression of TLR4,NF-κB and p38MAPK in the spinal cord of rats in each CTTP group was significantly lower than that in the model group(all P<0.05),and the relative expression of STAT3 protein was significantly higher than that in the model group(P<0.05).Conclusion CTTP is safety and can inhibit nociceptive sensitivity in rats with neuropathic pain induced by chronic sciatic nerve crush injury,and the mechanism may be related to inhibiting the expression of TLR4,NF-κB,p38MAPK and upregulating the expression of STAT3 in spinal cord.