title: Transient cerebral ischemia induces active astrocytosis without distinct neuronal death in the gerbil main olfactory bulb: a long-term analysis.
abstract: In the present study, we examined ischemia-induced neuronal and glial changes in the gerbil MOB at various time points during 60 days after 5 min of transient cerebral ischemia. The number of neuronal neuclei-immunoreactive neurons was not changed after ischemia/reperfusion (I/R). Myelin basic protein immunoreaction was well preserved after I/R. Five days after I/R, reactive form of GFAP-immunoreactive astrocytes began to increase in the external plexiform layer and granule cell layer: These reactive astrocytes peaked 10 days after I/R, thereafter, they decreased with time after I/R. Iba-1-immunoreactive microglia were ubiquitously distributed in all layers of the MOB. After I/R, significant changes in their morphology and immunoreactivity were not detected. The results of western blot analyses for GFAP, Iba-1 and MBP were similar to the immunohistochemical data. In addition, 8-hydroxy-2'-deoxyguanosine (a marker for DNA damage) immunoreactivity and SOD1, an antioxidant, protein levels were not changed in the ischemic MOB. These results indicate that neurons in the MOB are resistant to ischemic insult, showing that astrocytes are activated late in the ischemic MOB.
authors.affiliation: Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chuncheon, South Korea.
authors.forename: Jung Hoon
authors.initials: JH
authors.lastname: Choi
authors.forename: Ki-Yeon
authors.initials: KY
authors.lastname: Yoo
authors.forename: Choong Hyun
authors.initials: CH
authors.lastname: Lee
authors.forename: Ok kyu
authors.initials: Ok
authors.lastname: Park
authors.forename: Bing Chun
authors.initials: BC
authors.lastname: Yan
authors.forename: Hua
authors.initials: H
authors.lastname: Li
authors.forename: Yoo Sun
authors.initials: YS
authors.lastname: Moon
authors.forename: In Koo
authors.initials: IK
authors.lastname: Hwang
authors.forename: Yun Lyul
authors.initials: YL
authors.lastname: Lee
authors.forename: Hyung-Cheul
authors.initials: HC
authors.lastname: Shin
authors.forename: Moo-Ho
authors.initials: MH
authors.lastname: Won
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000378:metabolism / Q000473:pathology*; D016923:Cell Death; D005849:Gerbillinae; D005911:Gliosis; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D002546:Ischemic Attack, Transient / Q000473:pathology*; D008297:Male; D009474:Neurons / Q000378:metabolism / Q000473:pathology*; D009830:Olfactory Bulb / Q000378:metabolism / Q000473:pathology*