Age-related changes in nestin immunoreactivity in the rat pituitary gland

The pituitary gland undergoes important changes in cellular plasticity throughout life, consequently leading to hormonal output changes. The intermediate filament nestin plays a crucial role in cells that retain plasticity during development, aging and tumorigenesis. Here, we describe robust nestin immunoreactivity in glial-like cells of the intermediate lobe and in the vasculature of the developing, adult and aging pituitary gland. Additionally, we report a high incidence of spontaneous hyperplastic nodules in the anterior lobe of 24-month-old rats. In the nodules, nestin immunoreactivity is increased in blood vessels and in a few endocrine cells. We also found increased accumulation of nestin in hyperplastic glial-like cells of the intermediate lobe. This study suggests that nestin in the pituitary gland is implicated in age-related cellular plasticity.