【摘要】 目的:研究动物清醒状态下颌面部注射5%甲醛对大鼠诱发的伤害性行为反应特征与中枢神经元c-fos的表达情况。方法:将大鼠分为实验组(5%甲醛50μl右侧上唇区皮下注射)、对照组(0.9%生理盐水50μl右侧上唇区皮下注射)、冲动阻断组(1%Articain300μl右眶下区注射后10分钟再注射5%甲醛50μl)。观察注射后的伤害性行为反应———擦面反应和脑干c-fos的表达。结果:实验组大鼠出现明显的伤害性擦面反应,此行为反应呈典型的2个时相性:第一时相为注射后0～3min,经过一段平静期,12～42min为第二时相反应期;冲动阻断组仅有个别的伤害性行为反应;对照组无明确的伤害性行为反应。实验组在注射侧的三叉神经脊束核尾侧亚核(Vc)及腹侧髓质(VLM)可见大量的c-fos表达。冲动阻断组,两侧Vc及VLMc-fos表达数量及范围明显少于实验组。对照组未见c-fos表达。结论:清醒大鼠甲醛注射法可作为颌面部疼痛研究的动物实验模型。甲醛作为颌面疼痛刺激剂引发出的疼痛行为反应———擦面反应及中枢神经元c-fos表达,可否作为疼痛程度的指标,有待进一步研究。更多还原

【Abstract】 PURPOSE:To study the characters of nociceptive behavioral and c-fos expression in trigeminal nucleus fol-lowing formalin injection into subcutaneous tissue of vibrissa pad of unanesthetised Sprague-Dawley rats.METHODS:Control group(n=5)50μl0.9%saline was injected into the right vibrissa pad;Experimental group(n=5)50μl5%formalin was injected into right vibrissa pad;Impulse blocking group(n=5)50μl5%formalin was injected into right vibrissa pad10min after injection of1%Articaine300μl into the right infraorbital area.Each rat was observed for the nociceptive behav-ior-rubbing or grooming the site of injection and recorded its duration time(seconds)for every3minutes block after in-jection.Two hours after injection,brain stem was removed and c-fos immunohistochemistry was stained.RESULTS:The nociceptive behavioural responses of experimental group were typically biphasic:the first phase was0～3minutes after in-jection and the second phase was12～42minutes after a tranquil period.The expression of c-fos in experimental group was mainly located in ipsilateral trigeminal nucleus caudal(Vc).CONCLUSION:The method of formalin injection into o-rofacial area of unanesthetised animals is a suitable orofacial pain experimental model.Wether nociceptive behaviours or c-fos expression in trigeminal complex could be used as pain index needs to be further studied.更多还原