title: Dynamic Change in Cells Expressing IL-1β in Rat Hippocampus after Status Epilepticus.
abstract: BACKGROUND
  The time course of cytokine dynamics after seizure remains controversial. Here we evaluated the changes in the levels and sites of interleukin (IL)-1β expression over time in the hippocampus after seizure.
  
  
  METHODS
  Status epilepticus (SE) was induced in adult Wistar rats by means of intraperitoneal injection of kainic acid (KA). Subsequently, the time courses of cellular localization and IL-1β concentration in the hippocampus were evaluated by means of immunohistochemical and quantitative assays.
  
  
  RESULTS
  On day 1 after SE, CA3 pyramidal cells showed degeneration and increased IL-1β expression. In the chronic phase (>7 days after SE), glial fibrillary acidic protein (GFAP)-positive reactive astrocytes-appeared in CA1 and became IL-1β immunoreactive. Their IL-1β immunoreactivity increased in proportion to the progressive hypertrophy of astrocytes that led to gliosis. Quantitative analysis showed that hippocampal IL-1β concentration progressively increased during the acute and chronic phases.
  
  
  CONCLUSIONS
  IL-1β affects the hippocampus after SE. In the acute phase, the main cells expressing IL-1β were CA3 pyramidal cells. In the chronic phase, the main cells expressing IL-1β were reactive astrocytes in CA1.
authors.affiliation: Department of Pediatrics, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Sakuma
authors.affiliation: Department of Pediatrics, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Tokuhara
authors.affiliation: Division of Neurology, The Hospital for Sick Children, Toronto, Canada.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Otsubo
authors.affiliation: Department of Pediatrics, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Tsunekazu
authors.initials: T
authors.lastname: Yamano
authors.affiliation: Department of Pediatrics, Osaka City University Graduate School of Medicine, Osaka, Japan.
authors.forename: Haruo
authors.initials: H
authors.lastname: Shintaku
keywords: gliosis; hippocampus; interleukin-1β; reactive astrocyte; status epilepticus