Spatial clustering of substantia nigra astrocytes analyzed in rotenone model of hemiparkinsonism

Abstract

This paper addresses spatial aspects of reactive astrogliosis in the substantia nigra pars compacta (SNc) of the rat brain observed 40 and 70 days after the intracerebral 12 µg rotenone infusion. The infusion was shown to cause a marked increase in astrocyte density at both analyzed time points. Minimal spanning tree (MST) analysis was applied to analyze spatial patterns formed by nigral astrocytes. Spatial clusters of these cells, identified as disjoint MST subgraphs, were more numerous in the infused SNc tissue as compared with the control one. Size and density of clusters were significantly different between the infused and control areas 40 and 70 days after the infusion. In conclusion, the data suggests that rotenone-related astrogliosis in the substantia nigra includes changes in spatial patterns of astrocytes as well as transient spatial clustering of these cells.