Autoradiographic localization of receptors for neuropeptide FF, FLFQPQRFamide, in human spinal sensory system

• Published in: Brain research Vol. 633; no. 1; pp. 127 - 132
• Main Authors: Allard, M., Jordan, D., Zajac, J.M., Ries, C., Martin, D., Monkouanga, D., Kopp, N., Simonnet, G.
• Format: Journal Article
• Language: English
• Published: London Elsevier B.V 07.01.1994; Amsterdam Elsevier; New York, NY
• Subjects: Aged; Amino Acid Sequence; Animals; Antiopiate; Autoradiography; Biological and medical sciences; Brain Stem - metabolism; Child, Preschool; Fundamental and applied biological sciences. Psychology; Human; Humans; Infant; Male; Medulla Oblongata - metabolism; Molecular Sequence Data; Neurons, Afferent - metabolism; Neuropeptide FLFQPQRFamide; Neuropeptides - metabolism; Nociception; Oligopeptides - metabolism; Rats; Receptor; Receptors, Neuropeptide - metabolism; Somesthesis and somesthetic pathways (proprioception, exteroception, nociception); interoception; electrolocation. Sensory receptors; Spinal cord; Spinal Cord - metabolism; Vertebrates: nervous system and sense organs; Human; Nociception; Autoradiography; Spinal cord; Neuropeptide FLFQPQRFamide; Receptor; Antiopiate; Central nervous system; Cuneate nucleus; Neuropeptide; White matter; Goll nucleus; Somesthetic pathway; Peptidergic receptor; Medulla oblongata; Trigeminal nucleus
• ISSN: 0006-8993; 1872-6240
• DOI: 10.1016/0006-8993(94)91531-8

The regional distribution of FLFQPQRFamide binding sites on fresh unfixed cryostata sections from post mortem specimens of human spinal cord and lower medulla oblongata was studied by quantitative autoradiographic methods using [ 125I]YLFQPQRFamide as ligand. Samples were taken from fives cases who had died with no history of neurological disease at ages ranging from 5 months to 66 years. The biochemical and pharmacological characteristics of [ 125I]YLFQPQRFamide binding to mounted tissue sections were comparable to those reported for the rat in a previous study. [ 125I]YLFQPQRFamide appeared to interact reversibly with high affinity binding sites ( K d = 0.06nM ), distinct from opiate receptors. Sites labelled with [ 125I]YLFQPQRFamide were distributed unevenly within the human spinal cord and lower mmedulla oblongata, with the highest density in the superficial layers of the dorsal horn and the spinal trigeminal nucleus. Although moderate labelling was observed in the ventral part of spinal grey matter, dense labelling appeared in the gracile and cuneate nuclei. No binding sites were detected in white matter. These results show that, as in the rat, FLFQPQRFamide receptors in the human spinal cord and lower medulla oblongata, are mainly concentrated within spinal areas implicated in the analgesic action of opiates. The possible role of these receptors in modulating spinal nociceptive information is discussed with respect to the pharmacological effects of substances acting on FLFQPQRFamide receptors in animals.