多次联合注射可乐定与氯胺酮对单发性佐剂性关节炎的治疗作用

REPEATED INJECTION OF KETAMINE COMBINED WITH CLONIDINE FOR THE TREATMENT OF ADJUVANT MONOARTHRITIS IN RATS

目的：观察多次联合注射氯胺酮（ｋｅｔａｍｉｎｅ）及可乐定（ｃｌｏｎｉｄｉｎｅ）对关节炎的治疗作用。方法：用半剂量法设计实验，观察皮下联合注射氯胺酮（剂量固定）及可乐定（剂量变动）对单发性佐剂性关节炎的治疗作用。给药方式为每天皮下注射一次，每周５次，共治疗４周。疼痛评分采用背屈踝关节测痛试验，一周评分一次。动物的一般状况以体重增长速率为指标，炎症程度用踝周长表示。结果：（１）皮下联合注射氯胺酮（５ｍｇ／ｋｇ）及可乐定（２０μｇ／ｋｇ或者４０μｇ／ｋｇ）产生的镇痛效应显著大于单独注射氯胺酮（１０ｍｇ／ｋｇ）或可乐定（４０μｇ／ｋｇ或８０μｇ／ｋｇ）。（２）联合注射组动物的关节肿胀程度与单独注射可乐定或氯胺酮组无显著差异。（３）长期应用有协同镇痛作用的剂量组合对动物体重增长无明显影响。结论：氯胺酮与一定剂量的可乐定联合应用时具有显著的协同镇痛作用，但无协同消炎作用。有协同镇痛效应的剂量组合长期应用时对动物未产生明显的毒副作用。

Objective: To observe the effect of repeated combined injection of ketamine and clonidine for the treatment of rat adjuvant monoarthritis. Method: Rats with ankle monoarthritis were given subcutaneous(s.c.) injection of ketamine (fixed dose) and clonidine (varing doses), once a day, 5 times per week for a total of 4 weeks. Scores of pain were tested by dorsal flexion of ankle joint. Percent increase of body weight was taken as an index of general condition, and the swelling degree was expressed by the change of circumference of ankle. Results: (1) The combined injection of ketamine and clonidine in a ratio of 5mg/kg:20g/kg or 5mg/kg:40g/kg produced significantly more potent analgesia than that of injection of ketamine(10mg/kg) or clonidine(40 or 80g/kg) alone. (2) The sweelling degree of the inflamed ankle showed no significant difference between the combined injection group and the single injection group. (3) No significant changes were observed in body weight between the groups. Conclusions: Repeated injections of optimal combination of ketamine and clonidine produced synergistic analgesia without significant aversive side effects.