Expression of vimentin and glial fibrillary acidic protein in central nervous system development of rats.

Objective: To investigate the distribution and contents of vimentin (Vim) and glial fibrillary acidic protein (GFAP) immunoreactivities in the central nervous system (CNS) of normal newborn, adult and aged rats.

Methods: In this study, thirty healthy and normal Sprague-Dawley rats were simply classified into three groups: Newborn (7 days aged), adult (5 months aged) and aged (24 months aged) rats. Brains and spinal cord were dissected and cut into frozen sections. The expression of Vim and GFAP in CNS were detected by confocal immunofluorescence.

Results: In each group, Vim was expressed in all the regions of CNS including the hippocampal, cerebral cortex, the third ventricle and spinal cord, and the expression was highest in neuron-like cell of newborn rats, while Vim was mainly expressed in cell bodies in adult and aged rats. GFAP was expressed in all the regions of CNS including the hippocampal, cerebral cortex, the third ventricle and spinal cord, and the expression was in astrocytes of aged rats. In the third ventricle, Vim was detected in all groups, and only observed in neuron-like cells of newborn. Meanwhile, the GFAP expression showed no significant differences between adult and aged rats in this region. The co-localization of Vim and GFAP were mainly observed in hippocampus and cerebral cortex of newborn, but this co-localization was found in the third ventricle of the rats in all groups.

Conclusion: Our data demonstrate for the first time that the expression of Vim and GFAP in the rat's CNS during development. This data may provide a foundation for the further mechanistic studies of these two main intermediate filaments during development of CNS.