Spatiotemporal pattern of the postnatal astrogliogenesis in the rat hippocampal formation.

Newborn, 2-, 4-, 8-, 16- and 30-day-old Wistar rats were injected with 3H-thymidine and sacrificed following 4 h. survival time. Brain sections containing the dorsal part of hippocampal formation were immunostained for S-100beta protein and subjected to autoradiography to visualize proliferating astrocytes. Microscopical observations revealed age-dependent changes in the number and distribution of proliferating astrocytes. The changes were considered as being related to the neurogenetic gradient characteristic to the hippocampal formation.