Characterization of two novel tritiated radioligands for labelling Neuropeptide FF (NPFF(1) and NPFF(2)) receptors.
The binding characteristics of [(3)H]-NPVF and [(3)H]-EYF, the two first tritiated probes for the respective labelling of NPFF(1) and NPFF(2) receptors, are presented. In membranes from CHO cells transfected with the human NPFF(1) receptor, [(3)H]-NPVF labelled one class of binding sites with a high affinity (Bmax=4pmol/mg protein, Kd=2.65nM). In membranes from CHO cells transfected with the human NPFF(2) receptor, [(3)H]-EYF labelled one class of binding sites with a high affinity (Bmax=16pmol/mg protein, Kd=0.54nM). Both radioligands exhibited time-dependent binding, low (10-20%) non-specific binding and poor cross-reactivity towards the related receptor subtype. The potency of different NPFF ligands to displace [(3)H]-NPVF and [(3)H]-EYF binding profiles was in good agreement with the profile previously measured by using (125)I-probes (NPFF(1) receptor: NPVF> or =1DMe=SPA-NPFF>NPFF=SQA-NPFF=QFW-NPSF>NPSF>RF9; NPFF(2) receptor: SPA-NPFF>>SQA-NPFF=QFW-NPSF=1DMe=NPFF>>NPSF=NPVF>RF9). Therefore, [(3)H]-NPVF and [(3)H]-EYF are new valuable tools for performing binding on NPFF receptors.
Talmont
Franck
F
CNRS/IPBS (Institut de Pharmacologie et Biologie Structurale), 205 route de Narbonne 31077, Toulouse cedex 5, France; Université de Toulouse, UPS, 31077 Toulouse, France.
Garcia
Laura Piedra
LP
Mazarguil
Honoré
H
Zajac
Jean-Marie
JM
Mollereau
Catherine
C
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites / Q000502:physiology; D001667:Binding, Competitive / Q000187:drug effects / Q000502:physiology*; D016466:CHO Cells; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D006224:Cricetinae; D003412:Cricetulus; D003429:Cross Reactions; D005136:Eye Proteins / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008024:Ligands; D009479:Neuropeptides / Q000737:chemistry / Q000378:metabolism; D009842:Oligopeptides / Q000737:chemistry / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism; D011485:Protein Binding; D011869:Radioligand Assay / Q000379:methods*; D018013:Receptors, Neuropeptide / Q000378:metabolism*; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D013997:Time Factors; D014316:Tritium / Q000378:metabolism
C433725:EYWSLAAPQREF amide; D005136:Eye Proteins; D008024:Ligands; C452899:NPVF protein, human; D009479:Neuropeptides; D009842:Oligopeptides; D010446:Peptide Fragments; D018013:Receptors, Neuropeptide; C083929:neuropeptide FF receptor; D014316:Tritium; C053651:phenylalanyl-leucyl-phenylalanyl-glutaminyl-prolyl-glutaminyl-arginyl-phenylalaninamide