Apoptosis in the early involuting stellate reticulum of rat molar tooth germs

Página do item simplificado
dc.contributor.authorBaratella, L.
dc.contributor.authorArana-Chavez, V. E.
dc.contributor.authorKatchburian, E.
dc.contributor.institutionUniversidade Federal de São Paulo (UNIFESP)
dc.contributor.institutionUniversidade de São Paulo (USP)
dc.contributor.institutionUniv Ponta Grossa
dc.date.accessioned2016-01-24T12:30:50Z
dc.date.available2016-01-24T12:30:50Z
dc.date.issued1999-07-01
dc.description.abstractWhen the enamel organ of the rat tooth germ is fully developed at the tip of the prospective cusp, amelogenesis begins, and at this site the overlaying stellate reticulum begins its involution. During the involution process, there is a gradual decrease in intercellular spaces, invasion by blood vessels, appearance of macrophage-like cells and reduction in the number of stellate reticulum cells. Since reduction or disappearance of cells during embryonic development in organs and tissues has been shown to occur by apoptosis, we decided to examine early involuting regions of the stellate reticulum in the hope of detecting apoptosis. for this purpose, upper first molars of Wistar newborn rats aged 1 and 3 days were fixed in formaldehyde for the TUNEL method and in glutaraldehyde-formaldehyde for light and electron microscopy. Paraffin sections revealed TUNEL-positive structures, i.e. brown-yellow-stained bodies, in the central portion of the stellate reticulum, and next to the outer enamel epithelium and stratum intermedium. Examination of ultrathin sections confirmed the TUNEL findings: some stellate reticulum cells showed nuclei containing crescent-like electron-opaque condensed masses of peripheral chromatin, typical of apoptosis. Also, apoptotic bodies of various sizes and appearances were frequently observed within stellate reticulum cells. We should like to suggest that apoptosis is associated with the reduction in the number of cells during regression of the reticulum.en
dc.description.affiliationUniversidade Federal de São Paulo, Sch Med, Dept Morphol, BR-04023900 São Paulo, SP, Brazil
dc.description.affiliationUniv São Paulo, Dept Histol & Embryol, Inst Biomed Sci, BR-05508900 São Paulo, SP, Brazil
dc.description.affiliationUniv Ponta Grossa, Dept Biol, BR-84010100 Ponta Grossa, PR, Brazil
dc.description.affiliationUnifespUniversidade Federal de São Paulo, Sch Med, Dept Morphol, BR-04023900 São Paulo, SP, Brazil
dc.description.sourceWeb of Science
dc.format.extent49-54
dc.identifierhttp://dx.doi.org/10.1007/s004290050258
dc.identifier.citationAnatomy and Embryology. New York: Springer Verlag, v. 200, n. 1, p. 49-54, 1999.
dc.identifier.doi10.1007/s004290050258
dc.identifier.issn0340-2061
dc.identifier.urihttp://repositorio.unifesp.br/handle/11600/26102
dc.identifier.wosWOS:000080685700005
dc.language.isoeng
dc.publisherSpringer
dc.relation.ispartofAnatomy and Embryology
dc.rightsinfo:eu-repo/semantics/restrictedAccess
dc.rights.licensehttp://www.springer.com/open+access/authors+rights?SGWID=0-176704-12-683201-0
dc.subjectamelogenesisen
dc.subjectprogrammed cell deathen
dc.subjecttransmission electron microscopyen
dc.subjectenamel organen
dc.subjectrodent molar teethen
dc.titleApoptosis in the early involuting stellate reticulum of rat molar tooth germsen
dc.typeinfo:eu-repo/semantics/article
Arquivos
Coleções
Em verificação - Geral