title: Effects of adrenalectomy and replacement therapy of corticosterone on cell proliferation and neuroblast differentiation in the rat dentate gyrus.
abstract: Newly generated neurons in the dentate gyrus differentiate into mature granule cells. In the present study, we observed the effects of adrenalectomy (ADX) and corticosterone replacement therapy (CRT) on cell death, cell proliferation and neuroblast differentiation in the subgranular zone of the hippocampal dentate gyrus (SZDG). For this, the animals received vehicle or CRT after ADX, and were sacrificed 5 or 42 days later. Plasma corticosterone levels were very low in the adrenalectomized groups, whereas CRT after ADX significant increased serum corticosterone levels at 42 days, not 5 days, after ADX. ADX induced some neuronal damage in the dentate gyrus at 5 days post-ADX. CRT did not significantly reduce the neuronal damage at 5 days post-ADX; however, neuronal damage was not shown at 42 post-ADX with CRT. Ki67 (a marker for cell proliferation) and doublecortin (DCX, a marker for neuronal differentiation) immunoreaction was detected in the SZDG. ADX transiently increased cell proliferation and neuroblast differentiation 5 days after ADX, not 42 days, after ADX, and the CRT 42 days after ADX prominently decreased cell proliferation and neuroblast differentiation in the dentate gyrus. These results suggest that adrenal corticosteroid hormone is not essential for cell proliferation and neuroblast differentiation in long-term period after ADX.
authors.affiliation: Laboratory of Veterinary Pharmacology, College of Veterinary Medicine, Seoul National University, Seoul 151-742, South Korea.
authors.forename: Choong Hyun
authors.initials: CH
authors.lastname: Lee
authors.forename: Dae Young
authors.initials: DY
authors.lastname: Yoo
authors.forename: Ok Kyu
authors.initials: OK
authors.lastname: Park
authors.forename: Joon Ha
authors.initials: JH
authors.lastname: Park
authors.forename: Sun Shin
authors.initials: SS
authors.lastname: Yi
authors.forename: Yeo Sung
authors.initials: YS
authors.lastname: Yoon
authors.forename: Moo-Ho
authors.initials: MH
authors.lastname: Won
authors.forename: In Koo
authors.initials: IK
authors.lastname: Hwang
mesh_terms: D000315:Adrenalectomy; D000818:Animals; D016923:Cell Death / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects* / Q000502:physiology; D049109:Cell Proliferation / Q000187:drug effects*; D003345:Corticosterone / Q000378:metabolism / Q000494:pharmacology*; D018891:Dentate Gyrus / Q000166:cytology* / Q000502:physiology; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D055495:Neurogenesis / Q000187:drug effects / Q000502:physiology; D009474:Neurons / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D009479:Neuropeptides / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
chemical_list: C000714328:DCX protein, human; C000714848:Dcx protein, rat; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D019394:Ki-67 Antigen; D008869:Microtubule-Associated Proteins; D009479:Neuropeptides; D003345:Corticosterone