[P2-3-07] Differential changes in the induction of c-Fos and phosphorylated ERK in the trigeminal spinal tract nucleus after peripheral nerve injury
Keywords:中枢神経、疼痛、生理活性物質
This study was conducted to elucidate the influence of peripheral nerve insult on brainstem neurons. The brainstem was examined for neuronal profiles immunolabeled for c-Fos and phosphorylated ERK (p-ERK) elicited by stimulation of the tongue with capsaicin after lingual or inferior alveolar nerve injury. Abundant neuronal profiles labeled for c-Fos and p-ERK elicited by capsaicin were distributed in the subnucleus caudalis (Vc) of the spinal trigeminal tract nucleus without nerve injury. The subnucleus oralis (Vo) contained limited numbers of these neuronal profiles after stimulation. A significant reduction of these neuronal profiles in the ipsilateral Vc was detected after lingual nerve injury. After inferior alveolar nerve injury, an increased number of neuronal profiles labeled for c-Fos elicited by capsaicin was noted, while that of p-ERK was left unchanged in the ipsilateral Vc. On the both sides of the Vo, an increased number of capsaicin-induced neuronal profiles labeled for c-Fos and p-ERK was detected with both nerve injuries. These differential effects of nerve injury may be involved in the complex nature of symptoms of trigeminal neuralgia.