title: Altered sigma-1 receptor expression in two animal models of cognitive impairment.
abstract: OBJECTIVE
  Sigma-1 receptors are involved in learning and memory processes. We assessed sigma-1 receptor expression and memory function in two animal models of cognitive impairment.
  
  
  METHODS
  Male Wistar-Hannover rats were either lesioned by unilateral injection of N-methyl-D-aspartic acid in the nucleus basalis, or deprived of rapid eye movement sleep for 48 h, using the modified multiple platform method. Sigma-1 receptor expression was examined with the positron emission tomography radiotracer [(11)C]SA4503, immunohistochemistry, and Western blotting.
  
  
  RESULTS
  Cortical tracer uptake after 1 week was not significantly affected by lesioning. Immunohistochemistry revealed moderate increases of sigma-1 receptors at bregma level -2.8, in parietal cortex layer V of the lesioned hemisphere. Sleep deprivation lowered passive avoidance test scores and reduced [(11)C]SA4503 accumulation and sigma-1 receptor expression in pons.
  
  
  CONCLUSIONS
  Cholinergic lesioning causes an increase of sigma-1 receptor expression in a small cortical area which may be neuroprotective. Sleep deprivation decreases receptor expression in midbrain and pons.
authors.affiliation: Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands.
authors.forename: Nisha K
authors.initials: NK
authors.lastname: Ramakrishnan
authors.forename: Krisztina
authors.initials: K
authors.lastname: Marosi
authors.forename: Csaba J
authors.initials: CJ
authors.lastname: Nyakas
authors.forename: Chantal
authors.initials: C
authors.lastname: Kwizera
authors.forename: Philip H
authors.initials: PH
authors.lastname: Elsinga
authors.forename: Kiichi
authors.initials: K
authors.lastname: Ishiwata
authors.forename: Paul G M
authors.initials: PG
authors.lastname: Luiten
authors.forename: Rudi A J O
authors.initials: RA
authors.lastname: Dierckx
authors.forename: Aren
authors.initials: A
authors.lastname: van Waarde
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002794:Choline / Q000378:metabolism; D003072:Cognition Disorders / Q000378:metabolism*; D004195:Disease Models, Animal; D007700:Kinetics; D008297:Male; D017208:Rats, Wistar; D011930:Reaction Time; D017480:Receptors, sigma / Q000378:metabolism*; D012892:Sleep Deprivation / Q000378:metabolism; D013003:Somatosensory Cortex / Q000378:metabolism / Q000473:pathology; D014018:Tissue Distribution; D000097605:Sigma-1 Receptor
chemical_list: D002794:Choline; D017480:Receptors, sigma; D000097605:Sigma-1 Receptor