碳酸酐酶抑制剂乙酰唑胺对切口痛大鼠痛行为的影响

Effects of carbonic anhydrase inhibitor acetazolamide on pain behavior in a rat model of incision pain

目的观察鞘内注射碳酸酐酶抑制剂乙酰唑胺(ACT)对大鼠切口痛行为的影响。方法所有大鼠术前6天鞘内置管,随机分为5组:假手术组、假手术+ACT组、切口痛组、切口痛+ACT低剂量(2.25μg)组、切口痛+ACT高剂量(22.5μg)组,每组16只。按照Brennan法建立切口痛模型。ACT和生理盐水均在术后d 1鞘内给予。分别于术前d1(基础值)、术后d 1(给药前,给药后30、75、120、165、240min)测定大鼠的热缩足潜伏期(TWL)和机械缩足反射阈值(MWT),并予比较。结果切口痛术后d 1(给药前)与基础值相比TWL、MWT均明显降低(P<0.05);鞘内给予高剂量ACT,与给药前相比,给药后30、75、120 min TWL升高(P<0.05),但不影响大鼠的MWT;与切口痛组相比,切口痛+ACT高剂量组在给药后30、75、120 min TWL明显增高(P<0.05)。结论鞘内给予碳酸酐酶抑制剂ACT部分缓解了切口痛大鼠的热痛觉过敏,但是对机械痛觉过敏没有影响,提示碳酸酐酶可能参与了切口痛的热痛敏过程。

Aim To observe the effect of carbonic anhydrase inhibitor acetazolamide（ACT） on the behavior of rats with incision pain.Methods All rats were intrathecally cathetered,six days later they were randomly divided into 5 groups with 16 rats in each group： sham,sham＋ACT,incision pain,incision pain＋low dose of ACT（2.25 μg）,incision pain ＋high dose of ACT（22.5 μg）.Rat＇s incision pain model was established by using Brennan′s method.ACT or vehicle was administered intrathecally 24 h after operation.Thermal withdrawal latency（TWL） and mechanical withdrawal threshold（MWT） were measured and compared 1d before operation（baseline）and 1d after operation（before drug injection and 30,75,120,165,240 min after drug injection）.Results The TWL and MWT were decreased significantly on 1 d after incision compared with baseline（P0.05）.Intrathecal administration of high-dose ACT increased the TWL at 30,75 and 120 min after drug injection（P0.05）.However,high dose ACT had no effect on the MWT.The TWL in incision＋HACT group was significantly higher than that in incision group at 30,75 and 120 min after drug injection（P0.05）.Conclusions ACT at large dose can partially alleviate incision-induced heat hyperalgesia but has no effect on the mechanical hyperalgesia.Carbonic anhydrase might be involved in the development of heat hyperalgesia induced by incision.