An ultrastructural study of the choroid plexus of aged mice

The choroid plexus of mice aged 25, 28 and 31 months was examined in the transmission electron microscope. The main changes noted with age were the presence of lipid droplets, dense bodies and, much more rarely, vacuoles surrounded by a fine lamellar membrane. The cytoplasm of light choroid epithelial cells seemed more electron-dense than in young adults and the microvilli were long and slender in contrast with the short, spatulate microvilli seen in young mice. Glycogen was rarely present in choroid plexus cells in old age. The morphological changes suggest a decrease in efficiency of choroid plexus epithelial cells in old age.