Involvement of neurotrophic factors in the development of neuropathic pain evoked by the loose-ligation of peripheral nerves

点击翻译按钮获取中文摘要

It has been already known that various neurotrophic factors act on the repair of the damage site for neuronal regeneration following a peripheral nerve injury. In this study, therefore, to investigate whether or not neurotrophic factors affected the development and/or maintenance of such pathological pain states as the hyperalgesia and allodynia observed with peripheral nerve damage, loose-ligation on the left sciatic nerves of mouse were performed. The responses to thermal stimulation were then measured by the Plantar Test. Hypersensitivity to thermal stimulation developed on the ipsilateral side in ligated animals 3 days after surgery and lasted for at least 49 days. The direct application of neurotrophic factors such as oxidized galectin-1, artemin and platelet-derived neurotrophic factor (BDNF) at the nerve-ligation site showed remarkable inhibition against nerve injury-induced thermal hyperalgesia compared with the direct application of vehicle. Particularly, in the oxidized galectin-1 application group, marked analgesic effect was observed 3-28 days after application of this drug, that is, thermal hyperalgesia developed on the 31 days after injury. Unlike such result obtained by the oxidized galectin-1, however, in the group which applied artemin or platelet-derived neurotrophic factor (BDNF), prolongation of withdrawal latency (analgesic effect) was not observed