title: Ciproxifan, an H3 receptor antagonist, improves short-term recognition memory impaired by isoflurane anesthesia.
abstract: Exposure to volatile anesthetics has been reported to cause temporary or sustained impairments in learning and memory in pre-clinical studies. The selective antagonists of the histamine H3 receptors (H3R) are considered to be a promising group of novel therapeutic agents for the treatment of cognitive disorders. The aim of this study was to evaluate the effect of H3R antagonist ciproxifan on isoflurane-induced deficits in an object recognition task.
  
  
  
  Adult C57BL/6 J mice were exposed to isoflurane (1.3 %) or vehicle gas for 2 h. The object recognition tests were carried at 24 h or 7 days after exposure to anesthesia to exploit the tendency of mice to prefer exploring novel objects in an environment when a familiar object is also present. During the training phase, two identical objects were placed in two defined sites of the chamber. During the test phase, performed 1 or 24 h after the training phase, one of the objects was replaced by a new object with a different shape. The time spent exploring each object was recorded.
  
  
  
  A robust deficit in object recognition memory occurred 1 day after exposure to isoflurane anesthesia. Isoflurane-treated mice spent significantly less time exploring a novel object at 1 h but not at 24 h after the training phase. The deficit in short-term memory was reversed by the administration of ciproxifan 30 min before behavioral training.
  
  
  
  Isoflurane exposure induces reversible deficits in object recognition memory. Ciproxifan appears to be a potential therapeutic agent for improving post-anesthesia cognitive memory performance.
authors.affiliation: Department of Anesthesiology, Peking University Shenzhen Hospital, 1120 Lianhua Road, Shenzhen, Guangdong, China.|Anhui Medical University, Hefei, Anhui, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Ding
authors.affiliation: Department of Anesthesiology, Peking University Shenzhen Hospital, 1120 Lianhua Road, Shenzhen, Guangdong, China.
authors.forename: Limin
authors.initials: L
authors.lastname: Zheng
authors.affiliation: Shenzhen Advanced Medical Education Center, Shenzhen, Guangdong, China.
authors.forename: Min
authors.initials: M
authors.lastname: Liu
authors.affiliation: Department of Anesthesiology, Peking University Shenzhen Hospital, 1120 Lianhua Road, Shenzhen, Guangdong, China.
authors.forename: Rongfa
authors.initials: R
authors.lastname: Chen
authors.affiliation: Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada.
authors.forename: L Stan
authors.initials: LS
authors.lastname: Leung
authors.affiliation: Department of Anesthesiology, Peking University Shenzhen Hospital, 1120 Lianhua Road, Shenzhen, Guangdong, China. luotao_wh@yahoo.com.
authors.forename: Tao
authors.initials: T
authors.lastname: Luo
mesh_terms: D000758:Anesthesia / Q000009:adverse effects*; D000818:Animals; D007093:Imidazoles / Q000494:pharmacology*; D007530:Isoflurane / Q000633:toxicity*; D007858:Learning; D008297:Male; D008568:Memory / Q000187:drug effects*; D051379:Mice; D008810:Mice, Inbred C57BL; D018100:Receptors, Histamine H3 / Q000187:drug effects
chemical_list: D007093:Imidazoles; D018100:Receptors, Histamine H3; C115705:ciproxifan; D007530:Isoflurane
keywords: Ciproxifan; Isoflurane; Memory