title: Biphasic effect on nociception and antiopiate activity of the neuropeptide FF (FLFQPQRFamide) in the rat.
abstract: The purpose of the present study was to systematically investigate the effects of the mammalian neuropeptide Phe-Leu-Phe-Gln-Pro-Gln-Arg-Phe-NH2 (NPFF) on nociception, using the tail-flick test. We report that ICV administration of NPFF induces a rapid and short-lasting hyperesthesic effect during day or night, for doses ranging from 10 ng to 10 micrograms. During the night, this hyperesthesic effect is followed by a long-lasting analgesic effect, the magnitude of which is related to the magnitude of the hyperesthesic effect. In addition to this intrinsic effect of NPFF, we report that NPFF reverses morphine-induced analgesia and that the magnitude of the response elicited by NPFF increases as a function of morphine-induced analgesia.
authors.affiliation: INSERM U259, INSERM U176, Université de Bordeaux II, France.
authors.forename: P
authors.initials: P
authors.lastname: Oberling
authors.forename: L
authors.initials: L
authors.lastname: Stinus
authors.forename: M
authors.initials: M
authors.lastname: Le Moal
authors.forename: G
authors.initials: G
authors.lastname: Simonnet
mesh_terms: D000595:Amino Acid Sequence; D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D007276:Injections, Intraventricular; D008297:Male; D008969:Molecular Sequence Data; D009020:Morphine / Q000037:antagonists & inhibitors; D009292:Narcotic Antagonists / Q000494:pharmacology*; D009479:Neuropeptides / Q000494:pharmacology*; D009842:Oligopeptides / Q000494:pharmacology*; D010146:Pain / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
chemical_list: D000700:Analgesics; D009292:Narcotic Antagonists; D009479:Neuropeptides; D009842:Oligopeptides; D009020:Morphine; C053651:phenylalanyl-leucyl-phenylalanyl-glutaminyl-prolyl-glutaminyl-arginyl-phenylalaninamide