title: IgG from antiserum against endogenous mammalian FMRF-NH2-related peptides augments morphine- and stress-induced analgesia in mice.
abstract: Two mammalian FMRF-NH2-like peptides have been isolated from bovine brain; an octapeptide with the structure Phe-Leu-Phe-Gln-Pro-Gln-Arg-Phe-NH2 (F-8-F-NH2) and an octadecapeptide, Ala-Gly-Glu-Gly-Leu-Ser-Ser-Pro-Phe-Trp-Ser-Leu-Ala-Ala-Pro-Gln-Arg-Phe- NH2 (A-18-F-NH2). In the present study determinations were made of the effects of intracerebroventricular administration of IgG prepared from antisera raised against these peptides on nociception and morphine- and immobilization-induced opioid analgesia in mice. Both F-8-F-NH2-IgG and A-18-F-NH2-IgG antisera increased nociception (thermal response latency) and significantly augmented morphine- and immobilization-induced analgesia in a naloxone reversible manner, with F-8-F-NH2-IgG antisera having a greater effect than A-18-F-NH2-IgG antisera. These results provide further evidence that mammalian FMRF-NH2-like peptides function as endogenous opiate antagonists and have a role in the mediation of antinociception.
authors.affiliation: Division of Oral Biology, Faculty of Dentistry, University of Western Ontario, London, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Kavaliers
authors.forename: H Y
authors.initials: HY
authors.lastname: Yang
mesh_terms: D000698:Analgesia; D000818:Animals; D000906:Antibodies / Q000032:analysis*; D004357:Drug Synergism; D019835:FMRFamide; D007074:Immunoglobulin G / Q000008:administration & dosage / Q000032:analysis*; D007274:Injections, Intraperitoneal; D007276:Injections, Intraventricular; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009020:Morphine / Q000494:pharmacology*; D009270:Naloxone / Q000494:pharmacology; D009479:Neuropeptides / Q000276:immunology*; D009619:Nociceptors / Q000187:drug effects; D011930:Reaction Time / Q000187:drug effects; D013315:Stress, Psychological / Q000503:physiopathology*; D013997:Time Factors
chemical_list: D000906:Antibodies; D007074:Immunoglobulin G; D009479:Neuropeptides; D009270:Naloxone; D019835:FMRFamide; D009020:Morphine