title: Antioxidant enzymes are differently changed in experimental ischemic hippocampal CA1 region following repeated restraint stress.
abstract: Restraint stress induces physiological changes in the brain. In the present study, we observed the effects of repeated stress on ischemic damage associated with oxidative stress in gerbils. Animals were placed into restrainers for 5h (between 09:30 h and 14:30 h) for 21 consecutive days prior to 5 min of transient cerebral ischemia. Experimental groups were divided into 4 groups; 1) sham-operated control-group (sham-group), 2) ischemia-operated control-group (ischemia-group), 3) sham-operated stress-group (stressed-sham-group), and 4) ischemia-operated stress-group (stressed-ischemia-group). Serum corticosterone level in the ischemia-group was highest (330% vs the sham-group) at 12h post-ischemia, and serum corticosterone levels in the stressed-ischemia-group were significantly lower than the ischemia-group. Locomotor activity in the ischemia-group was significantly increased (300% vs the sham-group) at 1 day post-ischemia; however, locomotor activity in the stressed-ischemia-group was less increased compared to the ischemia-group. A few NeuN (neuron-specific soluble nuclear antigen)-positive ((+)) cells were found in the stratum pyramidale (SP) of the hippocampal CA1 region (CA1) 4 days post-ischemia in the ischemia-group; however, in the stressed-ischemia-group at 4 days post-ischemia, 83.8% of NeuN(+) neurons were found. In addition, we found a few Fluro-Jade B (a marker for neuronal degeneration)(+) and TUNEL(+) cells in the stressed-ischemia-group at 4 days post-ischemia. In gliosis, glial fibrillary acidic protein(+) astrocytes in the stressed-ischemia-groups was similar to the ischemia-groups; however, ionized calcium-binding adapter molecule 1(+) microglia in the stressed-ischemia-groups were much less activated than the ischemia-groups. Among antioxidants, Cu,Zn-superoxide dismutase (SOD1) immunoreactivity in the SP was higher in the stressed-ischemia-groups than the ischemia-groups. Catalase immunoreactivity in the SP of the stressed-ischemia-groups was similar to the ischemia-groups. However, Mn-superoxide dismutase and glutathione peroxidase immunoreactivity were lower than the ischemia-groups. In brief, our results indicate that repeated restraint stress significantly attenuates ischemic neuronal damage and locomotor activity following ischemia. In addition, SOD1 among antioxidants significantly increases in the stressed-ischemia-groups.
authors.affiliation: Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon 200-701, Republic of Korea.
authors.forename: Ki-Yeon
authors.initials: KY
authors.lastname: Yoo
authors.forename: Choong Hyun
authors.initials: CH
authors.lastname: Lee
authors.forename: Joon Ha
authors.initials: JH
authors.lastname: Park
authors.forename: In Koo
authors.initials: IK
authors.lastname: Hwang
authors.forename: Ok Kyu
authors.initials: OK
authors.lastname: Park
authors.forename: Seung-Hae
authors.initials: SH
authors.lastname: Kwon
authors.forename: Jung Hoon
authors.initials: JH
authors.lastname: Choi
authors.forename: Dae-joong
authors.initials: DJ
authors.lastname: Kim
authors.forename: Young-Guen
authors.initials: YG
authors.lastname: Kwon
authors.forename: Young-Myeong
authors.initials: YM
authors.lastname: Kim
authors.forename: Moo-Ho
authors.initials: MH
authors.lastname: Won
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D015153:Blotting, Western; D056547:CA1 Region, Hippocampal / Q000098:blood supply / Q000201:enzymology* / Q000473:pathology; D002560:Cerebrovascular Circulation; D002908:Chronic Disease; D003345:Corticosterone / Q000097:blood; D005455:Fluorescent Antibody Technique; D005849:Gerbillinae; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D002546:Ischemic Attack, Transient / Q000201:enzymology* / Q000473:pathology; D008297:Male; D009043:Motor Activity / Q000502:physiology; D009457:Neuroglia / Q000201:enzymology / Q000378:metabolism; D018384:Oxidative Stress; D012149:Restraint, Physical; D013315:Stress, Psychological / Q000201:enzymology* / Q000473:pathology / Q000503:physiopathology
chemical_list: D000975:Antioxidants; D005904:Glial Fibrillary Acidic Protein; D003345:Corticosterone