title: Appearance of neuronal S-100 beta during development of the rat brain.
abstract: In addition to being an astroglial protein, S-100 beta is localised in distinct populations of neurons in the adult rat hindbrain. We report, here, the expression of S-100 beta in both neurons and glia of the rat brain during development. Prenatally, S-100 beta immunoreactivity was confined to glial cells close to the germinal zone. After birth, S-100 beta positive glial cells were seen mainly in the brainstem and cerebellum, while only a few were detected in cerebral cortex and hippocampus. The number of S-100 beta containing glial cells increased steadily during the first 2 postnatal weeks after which the adult pattern was attained. No S-100 beta containing neurons were present prenatally. The first S-100 beta containing neurons were seen in the mesencephalic trigeminal nucleus at postnatal day 1 (P1), and in the motor trigeminal nucleus at P3. Neuronal S-100 beta immunoreactivity in other nuclei was mostly attained from the 10th to the 21st postnatal day. The neuronal S-100 beta immunoreactivity was first detected in the cell nuclei during development, then increased in the cytoplasm with ages. A nuclear staining in many immunoreactive neurons persisted until the adult. It usually took 1 to 2 weeks for neuronal S-100 beta to attain the adult staining pattern, i.e., heavy staining of the cytoplasm and processes, after its appearance. The forebrain never contained S-100 beta positive neurons. The S-100 beta is first expressed in glial cells, suggesting it is primarily of the glial origin. Coupled with neurotrophic effects of the protein, the time course of neuronal S-100 beta expression during the critical period of neuronal development implies that it may be involved in neuronal differentiation and maturation.
authors.affiliation: Department of Anatomy and Cell Biology, University of Göteborg, Sweden. Qiner. Yang@anatcell.gu.se
authors.forename: Q
authors.initials: Q
authors.lastname: Yang
authors.forename: A
authors.initials: A
authors.lastname: Hamberger
authors.forename: S
authors.initials: S
authors.lastname: Wang
authors.forename: K G
authors.initials: KG
authors.lastname: Haglid
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D001933:Brain Stem / Q000166:cytology* / Q000196:embryology / Q000254:growth & development; D002455:Cell Division / Q000502:physiology; D002531:Cerebellum / Q000166:cytology* / Q000196:embryology / Q000254:growth & development; D005260:Female; D007150:Immunohistochemistry; D009457:Neuroglia / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism*; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D009418:S100 Proteins / Q000096:biosynthesis* / Q000276:immunology
chemical_list: D009418:S100 Proteins