Cerebellar Cortex Neurons and Microglia Reaction to Sevoflurane Anesthesia

Resumo

The cerebellum is a part of the brain that is very sensitive to the toxic effects of general anesthetics. The aim of this work was to evaluate the morphological response of neurons and microgliocytes in all layers of the cerebellar cortex to prolonged (6 h) exposure of sevoflurane (general anesthetic). It was shown that, after prolonged exposure of Wistar male rats to sevoflurane, structural and functional rearrangement were observed in all layers of the cerebellar cortex. In the molecular and ganglion layers the total density of neurons decreased. The number of morphologically altered cells of the molecular layer and Purkinje cells increased to 250 and 300%, respectively, due to both direct toxic effects of the anesthetic and disruption of interneuron connections. In the granular layer, the total density of the neuron population did not change and the number of morphologically altered neurons did not increase significantly. The number of microgliocytes revealed immunohistochemically increased significantly, and activation in response to neuronal death was weakly present. The absence of excessive activation of microgliocytes after prolonged exposure to sevoflurane is a positive result, since neuroinflammatory mediators are produced to a lesser extent and neurons do not experience additional damaging effects from microglia.