The effects of chronic corticosterone on hippocampal astrocyte numbers: a comparison of male and female Wistar rats.

Chronic stress an/or glucocorticoid administration produces atrophy of hippocampal neurons. However, evidence of the impact of glucocorticoids on glial cells, especially in both males and females, is limited. In the present study, we investigated the total percentage body weight, hippocampal volume and hippocampal astrocyte numbers following chronic corticosterone treatment in male and female Wistar rats. Males had greater left and right hippocampal volumes overall, but no effect on hippocampal volume was seen after corticosterone treatment. Total body weight was dose-dependently lower in both sexes, but the decrease was more prominent in male rats. Corticosterone treatment dose-dependently increased astrocyte numbers in the CA1 region, but not in the lateral and medial CA3 hippocampal regions. This increase was similar in both male and female rats. The astrogliosis observed following chronic corticosterone may have implications for extrasynaptic communication and neuron-glia interactions and is similar to changes in the astrocytic population observed in aged rats.