title: Expression of AMPA receptor subunits in hippocampus after status convulsion.
abstract: OBJECTIVE
  The expression of 2-amino-3-(5-methyl-3-oxo-1, 2-oxazol-4-yl) propanoic acid receptor (AMPAR) subunits in the hippocampus of naive immature and adult rats (IRs, ARs) was investigated after status convulsion (SC).
  
  
  METHODS
  Seizures were induced in IRs and ARs with intraperitoneal injections of lithium and pilocarpine. Rats were killed at four time points (3 h, 1 day, 3 days, and 7 days) after SC. The proportion of apoptotic cells was quantified by Annexin V-FITC apoptosis detection. The location and type of apoptotic cells were assessed by using terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling staining. Immunoblotting techniques were used to demonstrate changes in AMPAR subunit expression.
  
  
  RESULTS
  Severe seizures induced neuronal apoptosis in the hippocampus. The proportion of apoptotic cells in IRs was consistently lower than that in ARs after SC. The expressions of four AMPAR subunits in IRs were consistently lower than those in ARs before and after SC. SC for 1 h inhibited the expression of glutamate receptors (GluR1-4) in the hippocampus of IRs and ARs and altered the subunit composition of AMPARs. GluR2 was the predominant AMPAR subunit in the hippocampus of normal ARs, while the GluR2/3 subunits were predominantly expressed 7 days after SC. GluR3/4 subunits were mainly expressed in the hippocampus of normal IRs, which had the lowest levels of GluR2.
  
  
  CONCLUSIONS
  Immature brain was more resistant to seizure-induced neural damage. The time course of reduction and recovery differed for each subunit and was dependent on developmental stage. The increased expression of GluR2 could confer early but transient protection in the immature brain after SC.
authors.affiliation: Department of Neurology, Children's Hospital, Chongqing University of Medical Sciences, No.136 Zhongshan 2nd Road, Yu Zhong District, Chongqing, China. huyue915@163.com
authors.forename: Yue
authors.initials: Y
authors.lastname: Hu
authors.forename: Li
authors.initials: L
authors.lastname: Jiang
authors.forename: Hengsheng
authors.initials: H
authors.lastname: Chen
authors.forename: XiaoPing
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000367:Age Factors; D000375:Aging / Q000502:physiology*; D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D015153:Blotting, Western; D003292:Convulsants / Q000633:toxicity; D004195:Disease Models, Animal; D006624:Hippocampus / Q000378:metabolism; D020287:In Situ Nick-End Labeling; D051381:Rats; D017208:Rats, Wistar; D018091:Receptors, AMPA / Q000096:biosynthesis*; D013226:Status Epilepticus / Q000150:complications / Q000378:metabolism* / Q000473:pathology*
chemical_list: D003292:Convulsants; D018091:Receptors, AMPA