title: Cell cycle time and rate of entry of cells into mitosis in the small intestine of young rats.
abstract: Cell cycle time (T(C)) and the rate of entry of cells into mitosis (r(M)) in the jejunum and duodenum of young rats were investigated using the stathmokinetic method. The cell cycle times in the jejunum were 24.3 and 28.3 h in light and dark periods, respectively. Cell cycle times in the duodenum were 17.1 and 21.5 h in light and dark periods, respectively. Rates of entry of cells into mitosis in the jejunum were 1.2 and 1.1 cells/cell/h in light and dark periods and rates of entry of cells into mitosis in the duodenum were 1.4 and 1.8 cells/cell/h in light and dark periods, respectively. Although these changes to cell cycle time values are not statistically significant, the variation between the two periods should be considered in relation to its possible biological effects.
authors.affiliation: Departamento de Biologia Estrutural, Molecular e Genética, Setor de Ciências Biológicas e da Saúde, Universidade Estadual de Ponta Grossa, Paraná, Brazil.
authors.forename: A C M
authors.initials: AC
authors.lastname: Wille
authors.forename: F A
authors.initials: FA
authors.lastname: Oliveira
authors.forename: M A M
authors.initials: MA
authors.lastname: Soares
authors.forename: J R
authors.initials: JR
authors.lastname: Gomes
mesh_terms: D000221:Adaptation, Ocular / Q000502:physiology / Q000528:radiation effects; D000818:Animals; D002453:Cell Cycle / Q000502:physiology* / Q000528:radiation effects; D002940:Circadian Rhythm / Q000502:physiology* / Q000528:radiation effects; D003623:Dark Adaptation / Q000502:physiology / Q000528:radiation effects; D004386:Duodenum / Q000166:cytology / Q000254:growth & development / Q000528:radiation effects; D005260:Female; D007413:Intestinal Mucosa / Q000166:cytology* / Q000254:growth & development / Q000528:radiation effects; D007421:Intestine, Small / Q000166:cytology* / Q000254:growth & development / Q000528:radiation effects; D007583:Jejunum / Q000166:cytology / Q000254:growth & development / Q000528:radiation effects; D008297:Male; D008938:Mitosis / Q000502:physiology* / Q000528:radiation effects; D010507:Periodicity; D010775:Photic Stimulation; D051381:Rats