title: [Effects of chronic hypoxic hypercapnia on spatial learning-memory and expression of NMDAR1 in rats].
abstract: OBJECTIVE
  To explore the effect of chronic hypoxic hypercapnia on learning-memory and the possible mechanisms involved.
  
  
  METHODS
  Fifty-eight male SD rats were randomly divided into three groups: Normal control group (NC, n=18), 2-week (2HH, n=18), and 4-week hypoxic hypercapnia (4HH, n=20) group. The rats, spatial learning-memory tasks were assessed by the Morris water maze. The expression of NMDAR1mRNA was determined by hybridization in situ.
  
  
  RESULTS
  Compared with NC group, rats exposed to chronic hypoxic hypercapnia displayed significant impairment in their performance assessed by two measures: mean escape latencies (2HH: 38.59 +/- 8.35 s, 4HH: 60.59 +/- 17.28 s) and swim path distances(2HH: 9893.45 +/- 1958.16 mm, 4HH: 18077.57 +/- 6878.85 mm). The expression level of NMDAR1mRNA in the hippocampus and cortex were lower than those in the NC group, especially, the NMDAR1mRNA expression of hippocampus CA1 in 4HH decreased by 21.4% (P < 0.01).
  
  
  CONCLUSIONS
  Chronic hypoxic hypercapnia could impair the rat spatial learning-memory and the decrease in expression of NMDAR1mRNA might be involved in.
authors.affiliation: Department of Neurology of the Second Affiliated Hospital of Wenzhou Medical College, China.
authors.forename: Song-fang
authors.initials: SF
authors.lastname: Chen
authors.forename: Sheng-min
authors.initials: SM
authors.lastname: Shao
authors.forename: Zhi-pen
authors.initials: ZP
authors.lastname: Wu
authors.forename: Han-jin
authors.initials: HJ
authors.lastname: Huang
authors.forename: Xiao-tong
authors.initials: XT
authors.lastname: Wang
authors.lastname: Li-yong
authors.forename: Yong-sheng
authors.initials: YS
authors.lastname: Gong
authors.forename: Guo-qing
authors.initials: GQ
authors.lastname: Zheng
mesh_terms: D000818:Animals; D006935:Hypercapnia / Q000378:metabolism*; D000860:Hypoxia / Q000378:metabolism*; D008297:Male; D018782:Maze Learning; D008568:Memory; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*
chemical_list: D016194:Receptors, N-Methyl-D-Aspartate