右美托咪定对甲醛炎性疼痛小鼠免疫功能的影响

Effect of dexmedetomidine on immune function in rats with formaldehyde-induced pain

目的观察右美托咪定对甲醛炎性疼痛小鼠免疫功能的影响。方法28只雄性C57BL/6健康小鼠随机均分为四组:NS组腹腔内注射生理盐水;D1、D2和D3组腹腔内分别注射右美托咪定10、20和30μg/kg。30min后,在小鼠右后掌皮下注射2%甲醛20μl(溶于生理盐水中)。评估右美托咪定的镇痛效果。检测乳酸脱氢酶(LDH)释放率(效靶比取80∶1、40∶1和20∶1)。溴脱氧尿苷(BrdU)掺入法检测脾淋巴细胞对植物血凝素(PHA)刺激诱导的增殖水平。结果与NS组比较,D1、D2和D3组对急性疼痛和痛觉过敏两个阶段都有相似的镇痛作用(P<0.01)。与NS组相比,D3组自然杀伤(NK)细胞的活性降低(P<0.05),D1、D2组NK细胞活性无统计学差异(P>0.05)。D1、D2和D3组对脾淋巴细胞的增殖反应差异无统计学意义(P>0.05)。结论右美托咪定30μg/kg能降低NK细胞毒性,但对淋巴细胞增殖功能没有明显影响。

Objective To investigate the effect of dexmedetomidine on immune function in rats with formaldehyde-induced pain. Methods Twenty-eight C57BL mice were equally divided into four groups. The rats in groups of D1, D2 and D3 were intraperitoneally injected dexmedetomidine 10,20 and 30μg/kg. The rats in group NS were given normal saline as the controls. At 30 minutes after injection, the pain was induced by injection of 2% formaldehyde 20/d in saline in all rats. The pain was evaluated, the activity of splenic natural killer（NK） cells against NK-sensitive YAC-1 lymphoma cells was evaluated by the percentage of specific lactate dehydrogenase（LDH） release（effect-target ratios were 80 ： 1,40 ： 1 and 20 ： 1）, and the level of lymphocyte proliferation in response to phytohema- gglutinin（PHA） was detected by bromodeoxyuridine（BrdU） incorporation assay. Results Compared to group NS, groups of D], I：）2 and D3 showed similar analgesic and antinociceptive effects in two phases（P^0. 01）. Compared to group NS, the activity of NK cells under pain condition was reduced in group D3（P〈0. 05）,which was not in groups of D1 and D2（P〉0. 05）. The proliferative response of the splenic lymphocytes of groups of D1, D2 and D3 was not affected compared with group NS （P〉0. 05）. Conclusion Dexrnedetomidine 30μg/kg can reduce the cytotoxicity of NK cells without significant effect on the proliferation of lymphocytes.