title: Post-ischemic hypothermia delayed neutrophil accumulation and microglial activation following transient focal ischemia in rats.
abstract: Following ischemia, inflammation has been demonstrated to be involved in the progression of the tissue damage. Intra-ischemic hypothermia has been shown to attenuate the adverse activities of neutrophils and microglia. We investigated whether neutrophil accumulation and/or microglial activation is attenuated in post-ischemic hypothermia following transient focal ischemia in rats. After 1 h of ischemia, the neutrophil accumulation and the microglial activation was evaluated immunohistochemically. Percent infarct area was compared at 1, 2, 3, 5, and 7 days after ischemia/reperfusion. In hypothermia, the neutrophil accumulation was delayed but not attenuated. In normothermia, the accumulation reached the peak at 2 days after ischemia. The peak shifted to 3 days in hypothermia. Similarly, the microglial activation was delayed in hypothermia. Comparison of the infarct area showed significant protection by hypothermia at 1 and 2 days after reperfusion. However, hypothermia failed to show significant protection after 3 days and later. These results show that the delayed neutrophil accumulation and the microglial activation can be responsible for the loss of persistent protection in post-ischemic hypothermia.
authors.affiliation: Department of Neurosurgery, Keio University School of Medicine, Shinanomachi 35, Shinjuku-ku, 160-8582, Tokyo, Japan. georges@med.keio.ac.jp
authors.forename: J
authors.initials: J
authors.lastname: Inamasu
authors.forename: S
authors.initials: S
authors.lastname: Suga
authors.forename: S
authors.initials: S
authors.lastname: Sato
authors.forename: T
authors.initials: T
authors.lastname: Horiguchi
authors.forename: K
authors.initials: K
authors.lastname: Akaji
authors.forename: K
authors.initials: K
authors.lastname: Mayanagi
authors.forename: T
authors.initials: T
authors.lastname: Kawase
mesh_terms: D000818:Animals; D015415:Biomarkers; D001772:Blood Cell Count; D002540:Cerebral Cortex / Q000098:blood supply / Q000166:cytology / Q000276:immunology; D002544:Cerebral Infarction / Q000276:immunology / Q000473:pathology / Q000628:therapy; D007036:Hypothermia, Induced; D007150:Immunohistochemistry; D002546:Ischemic Attack, Transient / Q000276:immunology* / Q000473:pathology / Q000628:therapy*; D008297:Male; D017628:Microglia / Q000166:cytology* / Q000276:immunology; D009504:Neutrophils / Q000166:cytology* / Q000276:immunology; D051381:Rats; D017208:Rats, Wistar
chemical_list: D015415:Biomarkers