Effects of morphine on the distribution of Fos protein in the trigeminal subnucleus caudalis neurons during experimental tooth movement of the rat molar

摘要: The present study was undertaken to disclose temporal changes in the distribution of Fos-like immunoreactive (-IR) neurons trigeminal subnucleus caudalis (SpVc), one important relay nuclei for processing nociceptive information from oro-facial regions, following induction experimental tooth movement rat upper molars. Furthermore, effect morphine and naloxone on levels Fos-IR SpVc examined. induced by insertion an elastic rubber between first second In normal animals, were rarely observed SpVc. Immediately after band, comparable that animals. number increased significantly 1 4 h movement, reaching a maximum at 2 h, then decreasing gradually. Most localized dorsomedial portion superficial layers ipsilateral near obex, but few ventral contralateral also showed immunoreactivity, their numbers smaller than those side. Pretreatment with (3 10 mg/kg, i.p.) reduced dose-dependent manner, its antagonized subsequent treatment (2 i.p.). Naloxone pretreatment enhanced expression results reduction suggest may be due noxious stimulation caused movement.