Structure-activity relationships of neuropeptide FF: role of C-terminal regions.
A structure-activity study was carried out to determine the importance of the C-terminal amino acids of the octapeptide Neuropeptide FF (NPFF) in binding and agonistic activity. Affinities of NPFF analogues were tested toward NPFF receptors of the rat spinal cord and the human NPFF2 receptors transfected in CHO cells. The activities of these analogues were evaluated by their ability to both inhibit adenylate cyclase in NPFF2 receptor transfected CHO cells and to reverse the effect of nociceptin on acutely dissociated rat dorsal raphe neurons. The substitutions of Phenylalanine8 by a tyrosine, phenylglycine or homophenylalanine were deleterious for high affinity. Similarly, the replacement of Arginine7 by a lysine or D. Arginine induces a loss in affinity. The pharmacological characterization showed that the presence of the amidated Phe8 and Arg7 residues are also extremely critical for activation of anti-opioid effects on dorsal raphe neurons. The sequence of the C-terminal dipeptide seems also to be responsible for the high affinity and the activity on human NPFF2 receptors. The results support the view that a code messaging the molecular interaction toward NPFF-receptors is expressed in the C-terminal region of these peptides but the N-terminal segment is important to gain very high affinity.
Mazarguil
H
H
Institut de Pharmacologie et de Biologie Structurale, CNRS UMR 5089, 205 Route de Narbonne, 31077, Toulouse Cedex, France.
Gouardères
C
C
Tafani
J A
JA
Marcus
D
D
Kotani
M
M
Mollereau
C
C
Roumy
M
M
Zajac
J M
JM
D000067956:Adenylyl Cyclase Inhibitors; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D001345:Autoradiography; D001667:Binding, Competitive; D016466:CHO Cells; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D006224:Cricetinae; D003412:Cricetulus; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D009842:Oligopeptides / Q000737:chemistry* / Q000494:pharmacology*; D018847:Opioid Peptides / Q000819:agonists; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000737:chemistry / Q000502:physiology*; D011903:Raphe Nuclei / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D018013:Receptors, Neuropeptide / Q000187:drug effects* / Q000378:metabolism; D011957:Receptors, Opioid / Q000819:agonists; D013116:Spinal Cord / Q000187:drug effects* / Q000378:metabolism; D013329:Structure-Activity Relationship; D014162:Transfection; D000097629:Nociceptin
D000067956:Adenylyl Cyclase Inhibitors; D009842:Oligopeptides; D018847:Opioid Peptides; D010446:Peptide Fragments; D018013:Receptors, Neuropeptide; D011957:Receptors, Opioid; D000097629:Nociceptin; C083929:neuropeptide FF receptor; C053651:phenylalanyl-leucyl-phenylalanyl-glutaminyl-prolyl-glutaminyl-arginyl-phenylalaninamide