title: Reduced hippocampal MT2 melatonin receptor expression in Alzheimer's disease.
abstract: The aim of the present study was to identify the distribution of the second melatonin receptor (MT2) in the human hippocampus of elderly controls and Alzheimer's disease (AD) patients. This is the first report of immunohistochemical MT2 localization in the human hippocampus both in control and AD cases. The specificity of the MT2 antibody was ascertained by fluorescence microscopy using the anti-MT2 antibody in HEK 293 cells expressing recombinant MT2, in immunoblot experiments on membranes from MT2 expressing cells, and, finally, by immunoprecipitation experiments of the native MT2. MT2 immunoreactivity was studied in the hippocampus of 16 elderly control and 16 AD cases. In controls, MT2 was localized in pyramidal neurons of the hippocampal subfields CA1-4 and in some granular neurons of the stratum granulosum. The overall intensity of the MT2 staining was distinctly decreased in AD cases. The results indicate that MT2 may be involved in mediating the effects of melatonin in the human hippocampus, and this mechanism may be heavily impaired in AD.
authors.affiliation: Psychiatric University Clinic, University of Basel, Basel, Switzerland. egemen.savaskan@pukbasel.ch
authors.forename: Egemen
authors.initials: E
authors.lastname: Savaskan
authors.forename: Mohammed A
authors.initials: MA
authors.lastname: Ayoub
authors.forename: Rivka
authors.initials: R
authors.lastname: Ravid
authors.forename: Debora
authors.initials: D
authors.lastname: Angeloni
authors.forename: Franco
authors.initials: F
authors.lastname: Fraschini
authors.forename: Fides
authors.initials: F
authors.lastname: Meier
authors.forename: Anne
authors.initials: A
authors.lastname: Eckert
authors.forename: Franz
authors.initials: F
authors.lastname: Müller-Spahn
authors.forename: Ralf
authors.initials: R
authors.lastname: Jockers
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000378:metabolism*; D000918:Antibody Specificity; D002460:Cell Line; D004591:Electrophoresis, Polyacrylamide Gel; D006624:Hippocampus / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008856:Microscopy, Fluorescence; D044123:Receptor, Melatonin, MT2 / Q000276:immunology / Q000378:metabolism*; D011994:Recombinant Proteins / Q000276:immunology / Q000378:metabolism
chemical_list: D044123:Receptor, Melatonin, MT2; D011994:Recombinant Proteins