Vaccarino A L, Chorney D A
Department of Psychology, University of New Orleans, LA 70148.
Brain Res. 1994 Dec 12;666(1):104-8. doi: 10.1016/0006-8993(94)90288-7.
Subcutaneous injection of formalin produces a biphasic profile of pain response: a transient early phase followed by a tonic late phase. A number of studies have indicated that the development of the late phase of formalin pain is dependent upon prolonged changes in central neural function produced by neural activity that is generated during the early phase (i.e. central sensitization). In support of this, the present demonstrates that stimulation- or morphine-produced analgesia derived from the periaqueductal grey (PAG) during the early phase prevents the development of the phase. These results suggest that descending mechanisms of pain inhibition, as reflected by PAG stimulation- and morphine-produced analgesia, can prevent the development of central neural plasticity following injury.
短暂的早期阶段后接着是持续性的晚期阶段。许多研究表明，福尔马林疼痛晚期阶段的发展依赖于早期阶段产生的神经活动所导致的中枢神经功能的长期变化（即中枢敏化）。支持这一观点的是，目前的研究表明，早期阶段导水管周围灰质（PAG）产生的刺激或吗啡诱导的镇痛作用可防止该阶段的发展。这些结果表明，PAG刺激和吗啡诱导的镇痛作用所反映的下行性疼痛抑制机制可以防止损伤后中枢神经可塑性的发展。
