Smith Shad B, Crager Sara E, Mogil Jeffrey S
Department of Psychology Centre for Research on Pain, McGill University, 1205 Dr. Penfield Ave., Montreal QC, Canada H3A 1B1.
Life Sci. 2004 Apr 9;74(21):2593-604. doi: 10.1016/j.lfs.2004.01.002.
Mechanical allodynia, or hypersensitivity to tactile stimuli, is a frequent clinical symptom of neuropathy. Large interindividual differences have been observed in neuropathic pain, both in susceptibility to its development and in its severity. Identification of genetic factors relevant to this variability would be of obvious utility. Although many animal models of neuropathic pain following peripheral nerve injury have been developed, most involve intricate surgeries and are thus poorly suited for large-scale linkage mapping investigations in the mouse. Recently, a schedule of intraperitoneal injections of the chemotherapeutic agent, paclitaxel (Taxol(R)), has been shown to produce a long-lasting, bilateral neuropathy in the rat, featuring hypersensitivity to mechanical, thermal and cold stimuli. We present here a survey of the responses of 10 inbred mouse strains to paclitaxel injections. Virtually all strains developed statistically significant mechanical allodynia, with one strain, DBA/2J, exhibiting especially robust changes. Strain sensitivities to paclitaxel-induced mechanical allodynia were similar to those obtained previously using a surgical model of neuropathic pain, supporting our contention that genetic sensitivity to mechanical allodynia is independent of the precise mode of induction. Using sensitive DBA/2 mice and a resistant strain, C57BL/6J, for comparison, we further characterized the paclitaxel model in mice by examining cold allodynia and thermal hyperalgesia. Both strains displayed equivalent cold allodynia but neither strain developed thermal hyperalgesia. The present data confirm a genetic component in mechanical allodynia using this model, while dissociating mechanical hypersensitivity from other pain modalities.
机械性异常性疼痛,即对触觉刺激的超敏反应,是神经病变常见的临床症状。在神经性疼痛方面,已观察到个体间存在很大差异,在其发生易感性和严重程度上均如此。鉴定与这种变异性相关的遗传因素将具有明显的实用价值。尽管已经建立了许多外周神经损伤后神经性疼痛的动物模型,但大多数模型涉及复杂的手术,因此不太适合在小鼠中进行大规模连锁图谱研究。最近,已证明腹腔注射化疗药物紫杉醇(泰素)的方案可在大鼠中产生持久的双侧神经病变,其特征为对机械、热和冷刺激敏感。我们在此展示了10个近交系小鼠品系对紫杉醇注射反应的调查结果。几乎所有品系都出现了具有统计学意义的机械性异常性疼痛,其中一个品系DBA/2J表现出尤为显著的变化。品系对紫杉醇诱导的机械性异常性疼痛的敏感性与先前使用神经性疼痛手术模型获得的敏感性相似,这支持了我们的观点,即对机械性异常性疼痛的遗传敏感性与诱导的精确方式无关。使用敏感的DBA/2小鼠和抗性品系C57BL/6J进行比较,我们通过检查冷异常性疼痛和热痛觉过敏进一步对小鼠中的紫杉醇模型进行了表征。两个品系均表现出同等程度的冷异常性疼痛,但均未出现热痛觉过敏。目前的数据证实了使用该模型时机械性异常性疼痛存在遗传成分,同时将机械性超敏反应与其他疼痛形式区分开来。