title: Pregnancy inhibits cell proliferation and neuroblast differentiation without neuronal damage in the hippocampal dentate gyrus in C57BL/6N mice.
abstract: Neural changes occur in the dam during gestation, and brain size has been shown to decrease across pregnancy in humans as well as rodents. In this study, we monitored neuronal damage, cell proliferation and neuroblast differentiation in the hippocampal dentate gyrus (DG) at age-matched virgin control (17- to 18-week-old), gestation day (GD) 14.5, 16.5 and 18.5 (17- to 18-week-old dams), using NeuN for mature neurons, terminal deoxynucleotidyl dUTP nick-end labeling (TUNEL) and Fluoro-Jade B (F-J B) for neuronal death, Ki67 for cell proliferation and doublecortin (DCX) for neuroblast differentiation in C57BL/6 mice. There were no significant differences in NeuN-immunoreactive ((+)) neurons between the age-matched control and gestating groups. TUNEL or F-J B positive neurons were rarely detected in the DG in all the groups. Ki67(+) cell proliferation was significantly decreased in the subgranular zone of the dentate gyrus (SZDG) at GD16.5. In addition, DCX(+) neuroblasts with/without tertiary dendrites were decreased in the SZDG with gestation by GD16.5. However, in the GD18.5 group, the number of Ki67(+) nuclei and DCX(+) neuroblasts with/without tertiary dendrites was slightly increased compared to that observed at GD16.5. DCX protein levels were low at GD16.5, and thereafter slightly increased. These results suggest that cell proliferation and neuroblast differentiation in DG of the hippocampus is decreased during gestation.
authors.affiliation: Department of Pediatrics, Kangnam Sacred Heart Hospital, College of Medicine, Hallym University, Seoul 150-950, South Korea.
authors.forename: Sung Koo
authors.initials: SK
authors.lastname: Kim
authors.forename: In Koo
authors.initials: IK
authors.lastname: Hwang
authors.forename: Ki-Yeon
authors.initials: KY
authors.lastname: Yoo
authors.forename: Dae Young
authors.initials: DY
authors.lastname: Yoo
authors.forename: Eunjoo
authors.initials: E
authors.lastname: Bae
authors.forename: Choong Hyun
authors.initials: CH
authors.lastname: Lee
authors.forename: Jung Hoon
authors.initials: JH
authors.lastname: Choi
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Choi
authors.forename: Je Kyung
authors.initials: JK
authors.lastname: Seong
authors.forename: Yeo Sung
authors.initials: YS
authors.lastname: Yoon
authors.forename: Moo-Ho
authors.initials: MH
authors.lastname: Won
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D004268:DNA-Binding Proteins; D003712:Dendrites / Q000502:physiology; D018891:Dentate Gyrus / Q000166:cytology / Q000502:physiology*; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D005260:Female; D005452:Fluoresceins; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D019394:Ki-67 Antigen / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism; D055495:Neurogenesis / Q000502:physiology*; D009474:Neurons / Q000166:cytology / Q000502:physiology*; D009479:Neuropeptides / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism; D009930:Organic Chemicals; D010784:Photomicrography; D011247:Pregnancy / Q000502:physiology*; D055153:Stem Cell Niche / Q000166:cytology / Q000502:physiology
chemical_list: C000714328:DCX protein, human; D004268:DNA-Binding Proteins; C000714847:Dcx protein, mouse; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D005452:Fluoresceins; D019394:Ki-67 Antigen; D008869:Microtubule-Associated Proteins; D009419:Nerve Tissue Proteins; C492380:NeuN protein, mouse; D009479:Neuropeptides; D009687:Nuclear Proteins; D009930:Organic Chemicals; C435731:fluoro jade