title: Effects of oxygen insufflation during pilocarpine-induced status epilepticus on mortality, tissue damage and seizures.
abstract: OBJECTIVE
  This prospective, randomized study was performed to investigate the effects of oxygen (O2) treatment during sustained epileptic activity on mortality, subsequent seizure frequency, and neuronal damage.
  
  
  METHODS
  Status epilepticus (SE) was induced by intraperitoneal injection of 340mg/kg pilocarpine, and terminated by diazepam after 40min. During SE, rats were randomized to O2 treatment (insufflation rate of 1.5l/min O2) during SE or normal air conditions. Outcome measures were SE-related mortality, seizure occurrence, mossy fiber sprouting, neuronal cell loss and expression of 27-kDa heat-shock protein (Hsp27).
  
  
  RESULTS
  O2-treated and O2-untreated animals did not differ with respect to SE latency, diazepam dose required to stop SE. While 7/38 rats died during SE in the O2-untreated group, very little mortality (1/38) occurred in the O2-treated group (P<0.05). However, within 1h after SE termination, seven O2-treated rats died which was not observed in the O2-untreated group indicating no significant difference in overall mortality. There was a tendency towards lower seizure rate in the O2-treated group at one month after pilocarpine-induced SE. Three months after SE, however, seizure rates were no longer different between both groups. Moreover, mossy fiber sprouting, neuronal cell loss and Hsp27 expression did not differ between O2-treated and O2-untreated groups.
  
  
  CONCLUSIONS
  Our findings indicate that O2 treatment might delay the relative risk of epileptic seizures following an initial brain injury, but it may also lead to a rather unfavorably increased heterogeneity of epileptogenesis in experimental studies.
authors: Oscar Langendorff Institute of Physiology, University of Rostock, Germany.
authors: Lorenz
authors: L
authors: Müller
authors: Oscar Langendorff Institute of Physiology, University of Rostock, Germany.
authors: Steffen
authors: S
authors: Müller
authors: Oscar Langendorff Institute of Physiology, University of Rostock, Germany.
authors: Tina
authors: T
authors: Sellmann
authors: Oscar Langendorff Institute of Physiology, University of Rostock, Germany.
authors: Linda
authors: L
authors: Groeneweg
authors: Oscar Langendorff Institute of Physiology, University of Rostock, Germany.
authors: Tursonjan
authors: T
authors: Tokay
authors: Oscar Langendorff Institute of Physiology, University of Rostock, Germany.
authors: Rüdiger
authors: R
authors: Köhling
authors: Oscar Langendorff Institute of Physiology, University of Rostock, Germany. Electronic address: timo.kirschstein@uni-rostock.de.
authors: Timo
authors: T
authors: Kirschstein
mesh_terms: D000818:Animals; D007327:Insufflation / Q000379:methods*; D008297:Male; D019599:Mossy Fibers, Hippocampal / Q000473:pathology*; D010100:Oxygen / Q000008:administration & dosage*; D010862:Pilocarpine / Q000633:toxicity*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012640:Seizures / Q000401:mortality / Q000473:pathology / Q000628:therapy; D013226:Status Epilepticus / Q000139:chemically induced / Q000401:mortality / Q000473:pathology* / Q000628:therapy*; D016896:Treatment Outcome
chemical_list: D010862:Pilocarpine; D010100:Oxygen
keywords: Heat-shock protein; Oxygen; Pilocarpine; Status epilepticus; Timm stain