Tooth pulp injury induces sex-dependent neuronal reshaping in the ventral posterolateral nucleus of the rat thalamus

Publication date: Available online 2 November 2018Source: Journal of Chemical NeuroanatomyAuthor(s): Ismael Juárez, Julio César Morales-Medina, Julia Flores-Tochihuitl, Gamaliel Santiago Juárez, Gonzalo Flores, Hortencia Chávez OsekiAbstractOrofacial injuries often result in persistent pain and are therefore considered a common health problem worldwide. Considerable evidence suggests that peripheral sensory nerve injury results in diverse plastic changes in the central nervous system (CNS). Tooth pulp is innervated by trigeminal afferents which extend to the trigeminal brainstem sensory nuclear complex and send input to higher level neurons in the CNS, including the ventral posterolateral nucleus of the thalamus (VPL). In the present study, we examined the long term effects of pulpal injury on neuronal arborization in the VPL using morphological analysis via Golgi-Cox staining. In addition, we examined these effects in both male and female rats due to the major prevalence of oral pain in women. Quantitative morphological analysis revealed that pulpal injury induced neuronal hypertrophy in VPL neurons of female rats. In clear contrast, pulpal injury increased arborization close to the soma and reduced arborization distal to the soma without modification of total dendritic length in male rats. As a result, we show, for the first time, sex-dependent morphological alterations in VPL neurons after orofacial peripheral injury. Since dental injuries are readily reproducible in r...
Source: Journal of Chemical Neuroanatomy - Category: Neuroscience Source Type: research