title: Hippocampal α7 nicotinic acetylcholine receptor levels in patients with schizophrenia, bipolar disorder, or major depressive disorder.
abstract: BACKGROUND
  The α7 nicotinic acetylcholine receptor (nAChR) is involved in cognitive function and synaptic plasticity. Consequently, changes in α7 nAChR function have been implicated in a variety of mental disorders, especially schizophrenia. However, there is little knowledge regarding the levels of the α7 nAChR in patients with bipolar disorder.
  
  
  METHODS
  We performed [(125)I]-bungarotoxin autoradiography to selectively visualize and measure α7 nAChRs on postmortem sections of the temporal lobe from patients with schizophrenia, bipolar disorder, or major depressive disorder, as well as control subjects. Radioligand binding was determined in the dentate gyrus, CA3, and CA1 subfields of the hippocampus and the perirhinal cortex.
  
  
  RESULTS
  Bungarotoxin binding was significantly increased in the CA1 and perirhinal cortex of patients with bipolar disorder compared to control subjects, whereas in patients with schizophrenia or major depressive disorder the level of binding did not significantly differ from control subjects in any region measured.
  
  
  CONCLUSIONS
  These data are consistent with the reported genetic associations linking the α7 nAChR to the pathology of bipolar disorder, and may suggest a dysfunction of α7 nAChR-dependent signalling in bipolar disorder. We could not reproduce the previously reported decrease in hippocampal bungarotoxin binding in schizophrenia.
authors.affiliation: Neurobiology Research Unit, University Hospital Copenhagen, Copenhagen, Denmark. morten.s.thomsen@nru.dk
authors.forename: Morten S
authors.initials: MS
authors.lastname: Thomsen
authors.forename: Annelies
authors.initials: A
authors.lastname: Weyn
authors.forename: Jens D
authors.initials: JD
authors.lastname: Mikkelsen
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001345:Autoradiography / Q000379:methods; D001714:Bipolar Disorder / Q000473:pathology*; D002038:Bungarotoxins / Q000493:pharmacokinetics; D003865:Major Depressive Disorder / Q000473:pathology*; D005260:Female; D005786:Gene Expression Regulation; D006624:Hippocampus / Q000000981:diagnostic imaging / Q000378:metabolism*; D006801:Humans; D007456:Iodine Isotopes / Q000493:pharmacokinetics; D008297:Male; D008875:Middle Aged; D011485:Protein Binding / Q000187:drug effects; D011877:Radionuclide Imaging; D011978:Receptors, Nicotinic / Q000378:metabolism*; D012559:Schizophrenia / Q000473:pathology*; D064569:alpha7 Nicotinic Acetylcholine Receptor
chemical_list: D002038:Bungarotoxins; C579167:Chrna7 protein, human; D007456:Iodine Isotopes; D011978:Receptors, Nicotinic; D064569:alpha7 Nicotinic Acetylcholine Receptor