Forebrain projections to brainstem nuclei involved in the control of mandibular movements in rats

Autor(es)

Mascaro, Marcelo B. ^{[1, 2]} ; Prosdocimi, Fabio C. ^[1] ; Bittencourt, Jackson C. ^[1] ; Elias, Carol F. ^{[1, 3]}

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Biomed Sci, Dept Anat, Sao Paulo - Brazil

^[2] Nove de Julho Univ, Coll Dent, BR-01504001 Sao Paulo - Brazil

^[3] Univ Texas SW Med Ctr Dallas, Dept Internal Med, Div Hypothalam Res, Dallas, TX 75390 - USA

• Tipo de documento: Artigo Científico
• Fonte: European Journal of Oral Sciences; v. 117, n. 6, p. 676-684, DEC 2009.
• Citações Web of Science: 13

Resumo

Mandibular movements occur through the triggering of trigeminal motoneurons. Aberrant movements by orofacial muscles are characteristic of orofacial motor disorders, such as nocturnal bruxism (clenching or grinding of the dentition during sleep). Previous studies have suggested that autonomic changes occur during bruxism episodes. Although it is known that emotional responses increase jaw movement, the brain pathways linking forebrain limbic nuclei and the trigeminal motor nucleus remain unclear. Here we show that neurons in the lateral hypothalamic area, in the central nucleus of the amygdala, and in the parasubthalamic nucleus, project to the trigeminal motor nucleus or to reticular regions around the motor nucleus (Regio h) and in the mesencephalic trigeminal nucleus. We observed orexin co-expression in neurons projecting from the lateral hypothalamic area to the trigeminal motor nucleus. In the central nucleus of the amygdala, neurons projecting to the trigeminal motor nucleus are innervated by corticotrophin-releasing factor immunoreactive fibers. We also observed that the mesencephalic trigeminal nucleus receives dense innervation from orexin and corticotrophin-releasing factor immunoreactive fibers. Therefore, forebrain nuclei related to autonomic control and stress responses might influence the activity of trigeminal motor neurons and consequently play a role in the physiopathology of nocturnal bruxism. (AU)

• Processo FAPESP: 05/50951-5 - Caracterizacao neuroquimica e hodologica dos neuronios que expressam o hormonio concentrador de melanina (mch) na area pre-optica durante a amamentacao.
• Beneficiário: Carol Fuzeti Elias
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 04/13849-5 - Circuitos peptidérgicos envolvidos na organização do comportamento alimentar
• Beneficiário: Jackson Cioni Bittencourt
• Modalidade de apoio: Auxílio à Pesquisa - Temático