RESUMO
Phenytoin is a commonly prescribed anticonvulsant drug; however, there is evidence that long-term administration is related to cerebellar ataxia, cerebellar atrophy, loss of Purkinje cells, and hyperplasia of Bergman glia cells. The aim of the present study was to detect and describe any possible alterations of the Purkinje cells, and neurons of the dentate nucleus, as those can be seen with the use of silver impregnation techniques, such as Golgi and Nauta method. The study was performed on a 7-year-old boy who was under phenytoin treatment for more than 3.5 years and had clinical manifestations of cerebellar ataxia. Golgi silver impregnation technique revealed substantial loss of dendritic spines and tertiary dendritic branches, both on the Purkinje cells and the neurons of the dentate nucleus, whereas the Nauta method demonstrated swollen and degenerated axons of Purkinje cells.
Assuntos
Anticonvulsivantes/uso terapêutico , Núcleos Cerebelares/efeitos dos fármacos , Epilepsia Tônico-Clônica/tratamento farmacológico , Fenitoína/uso terapêutico , Células de Purkinje/efeitos dos fármacos , Anticonvulsivantes/farmacologia , Axônios/efeitos dos fármacos , Axônios/patologia , Núcleos Cerebelares/patologia , Criança , Dendritos/efeitos dos fármacos , Dendritos/patologia , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/patologia , Epilepsia Tônico-Clônica/patologia , Humanos , Masculino , Fenitoína/farmacologia , Células de Purkinje/patologiaRESUMO
The visual cortex undergoes age related changes that have been studied mainly in rats Maccaca Mulata, and human beings. Despite the fact that there is no extensive neuronal loss in aged brains, a lot of important pathological changes are found in the morphology of the neurons. The present study describes the morphological alterations of the spiny stel-late cells of the human primary visual cortex during normal aging, using Golgi method, Golgi-Nissl staining and Nissl staining. Two types of spiny stellate cells have been studied. the first one located at layer 4Cß and the second one located at layer 4Cß. Even if some spiny stel-late cells retain high number of primary dendrites in the aged group there seems to be important spine loss, and extensive dendrite pathology. Age-related changes were more significant in spiny stellate cells of layer 4Cß. Dendritic and spinal alterations described in the present study could explain the decline in visual functions during normal aging.