Role of the Gonads in the Histologic Aging of the Hypothalamic Arcuate Nucleus1

Abstract

The effect of aging on microglial and astrocytic activity in the hypothalamic arcuate nucleus was measured in young and middle-aged Wistar rats and C57BL/6J mice. These putative correlates of neuronal degeneration increased significantly between 6 and 14 months of age in intact female and male rats, and between 4 and 13 months in female mice. Although astrocytic activity increased steadily between 4, 8.5, and 14 months in female rats, microglial activity did not increase until 14 months.