title: Morphofunctional changes of the astrocyte in rat hippocampus under different corticosteroid conditions.
abstract: In the present study, we examined the changes in the morphofunction of astrocytes in rat hippocampus under different circulating corticosteroid conditions by immunohistochemistry analysis of glial fibrillary acidic protein (GFAP) and ultra-high-voltage electron microscopy. Each GFAP-immunoreactive cell showed a hypertrophic appearance with well-developed thicker fibrous processes, and the number and the density of GFAP-immunoreactive cells were increased 4 weeks after adrenalectomy, whereas the changes were restored to the sham-control level with corticosterone replacement. The morphometric changes were observed in particular around the pyramidal neurons of CA1 and in the subgranular layer of dentate gyrus. The quantitative analysis clearly showed a significant increase in the number and the density of GFAP-immunoreactive cells in the adrenalectomy group; following corticosterone replacement, these increases were returned to the sham-control level. These changes were also specifically revealed by stereo-observation with ultra-high-voltage electron microscopy. The astrocyte showed more complicated fine three-dimensional branching after adrenalectomy. These results suggested that both the structure and function of astrocytes were modulated by corticosteroids via glucocorticoid receptor.
authors.affiliation: Department of Anatomy and Neurobiology, Nippon Medical School, 1-1-5 Sendagi, Tokyo 113-8602, Japan. yangchun@nms.ac.jp
authors.forename: Chun-Ying
authors.initials: CY
authors.lastname: Yang
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Matsuzaki
authors.forename: Norio
authors.initials: N
authors.lastname: Iijima
authors.forename: Naoko
authors.initials: N
authors.lastname: Kajimura
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Ozawa
mesh_terms: D000305:Adrenal Cortex Hormones / Q000378:metabolism*; D000315:Adrenalectomy; D000818:Animals; D001253:Astrocytes / Q000166:cytology* / Q000378:metabolism* / Q000648:ultrastructure; D002452:Cell Count; D003345:Corticosterone / Q000378:metabolism / Q000494:pharmacology; D018891:Dentate Gyrus / Q000166:cytology / Q000378:metabolism; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism*; D006624:Hippocampus / Q000166:cytology* / Q000378:metabolism; D008297:Male; D008854:Microscopy, Electron / Q000379:methods; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000305:Adrenal Cortex Hormones; D005904:Glial Fibrillary Acidic Protein; D003345:Corticosterone