Quantitative Evaluation of Changes in the Striatal Astrocyte Axons in Simulated Parkinsonism

Resumo

Three parkinsonism models using neurotoxin 6-OHDA and pesticides rotenone and paraquat were reproduced in Wistar rats and parameters of astrocyte processes in the striatum (axon number and length, area occupied by them, and axon branching pattern) detected by immunohistochemical reaction for acid glial fibrillary protein were studied by computer morphometry. By these parameters, three morphological types of astrocytes were distinguished. Two variants of changes were found in the used parkinsonism models: 1) more intense branching and even elongation of all axons and 2) reduction of small and elongation of the main remaining stems, which manifested in polarization of glial cell. Type 1 reaction was obviously associated with compensatory increase in astrocyte interaction with neurons, while type 2 reflected astrocyte response to injury and impaired glioneuronal interactions.