title: Preclinical evaluation of [11C]NE40, a type 2 cannabinoid receptor PET tracer.
abstract: BACKGROUND
  Up-regulation of the type 2 cannabinoid receptor (CB(2)R) has been reported in (neuro)inflammatory diseases. In this study, we report the preclinical evaluation of [(11)C]NE40 as positron emission tomography (PET) radioligand for visualization of the CB(2)R.
  
  
  METHODS
  The selectivity of NE40 for CB(2)R and its toxicity and mutagenicity were determined. [(11)C]NE40 was evaluated by biodistribution and autoradiography studies in normal rats and a microPET study in normal mice, rats and a rhesus monkey. Specific in vivo binding of [(11)C]NE40 to human CB(2)R (hCB(2)R) was studied in a rat model with hCB(2)R overexpression.
  
  
  RESULTS
  [(11)C]NE40 shows specific CB(2)R binding in the spleen and blood of normal rats and high brain uptake in rhesus monkey. [(11)C]NE40 showed specific and reversible binding to hCB(2)R in vivo in a rat model with local hCB(2)R overexpression.
  
  
  CONCLUSIONS
  [(11)C]NE40 shows favorable characteristics as radioligand for in vivo visualization of the CB(2)R and is a promising candidate for hCB(2)R PET imaging.
authors.affiliation: Laboratory for Radiopharmacy, K.U. Leuven, Leuven, Belgium BE3000.
authors.forename: Nele
authors.initials: N
authors.lastname: Evens
authors.forename: Caroline
authors.initials: C
authors.lastname: Vandeputte
authors.forename: Charlotte
authors.initials: C
authors.lastname: Coolen
authors.forename: Peter
authors.initials: P
authors.lastname: Janssen
authors.forename: Raf
authors.initials: R
authors.lastname: Sciot
authors.forename: Veerle
authors.initials: V
authors.lastname: Baekelandt
authors.forename: Alfons M
authors.initials: AM
authors.lastname: Verbruggen
authors.forename: Zeger
authors.initials: Z
authors.lastname: Debyser
authors.forename: Koen
authors.initials: K
authors.lastname: Van Laere
authors.forename: Guy M
authors.initials: GM
authors.lastname: Bormans
mesh_terms: D000818:Animals; D001345:Autoradiography / Q000379:methods; D001667:Binding, Competitive; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism; D002250:Carbon Radioisotopes; D002460:Cell Line; D005260:Female; D057809:HEK293 Cells / Q000378:metabolism; D006801:Humans; D008253:Macaca mulatta; D008297:Male; D051379:Mice; D049268:Positron-Emission Tomography / Q000379:methods; D011804:Quinolines / Q000097:blood / Q000493:pharmacokinetics* / Q000633:toxicity*; D011869:Radioligand Assay / Q000379:methods; D019275:Radiopharmaceuticals / Q000097:blood / Q000493:pharmacokinetics* / Q000633:toxicity*; D051381:Rats; D017208:Rats, Wistar; D043885:Receptor, Cannabinoid, CB2 / Q000032:analysis / Q000378:metabolism*; D014018:Tissue Distribution
chemical_list: C576981:2-oxo-7-methoxy-8-butyloxy-1,2-dihydroquinoline-3-carboxylic acid cyclohexylamide; D002250:Carbon Radioisotopes; D011804:Quinolines; D019275:Radiopharmaceuticals; D043885:Receptor, Cannabinoid, CB2