title: Mu and kappa1 opioid-stimulated [35S]guanylyl-5'-O-(gamma-thio)-triphosphate binding in cynomolgus monkey brain.
abstract: Agonist-stimulated [35S]GTPgammaS binding allows the visualization of receptor-activated G-proteins, thus revealing the anatomical localization of functional receptor activity. In the present study, agonist-stimulated [35S]GTPgammaS binding was used to demonstrate mu and kappa1 opioid-stimulated [35S]GTPgammaS binding in tissue sections and membranes from cynomolgus monkey brain using DAMGO and U50,488H, respectively. Concentrations of agonists required to produce maximal stimulation of [35S]GTPgammaS binding were determined in membranes from the frontal poles of the brain. Receptor specificity was verified in both membranes and sections by inhibiting agonist-stimulated [35S]GTPgammaS binding with the appropriate antagonist. Mu opioid-stimulated [35S]GTPgammaS binding was high in areas including the amygdala, ventral striatum, caudate, putamen, medial thalamus and hypothalamus. Dense mu-stimulated [35S]GTPgammaS binding was also found in brainstem nuclei including the interpeduncular nucleus, parabrachial nucleus and nucleus of the solitary tract. Kappa1 opioid-stimulated [35S]GTPgammaS binding was high in limbic and association cortex, ventral striatum, caudate, putamen, globus pallidus, claustrum, amygdala, hypothalamus and substantia nigra. These results demonstrate the applicability of [35S]GTPgammaS autoradiography to examine receptor-activated G-proteins in the primate brain and reveal functional mu and kappa1 opioid receptor activity that may contribute to the reported central nervous system effects of opiates.
authors.affiliation: Pharmacology and Toxicology Department and Institute for Drug and Alcohol Studies, Virginia Commonwealth University Medical College of Virginia, Richmond 23298, USA. ljsimsel@hsc.vcu.edu
authors.forename: L J
authors.initials: LJ
authors.lastname: Sim-Selley
authors.forename: J B
authors.initials: JB
authors.lastname: Daunais
authors.forename: L J
authors.initials: LJ
authors.lastname: Porrino
authors.forename: S R
authors.initials: SR
authors.lastname: Childers
mesh_terms: D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer / Q000494:pharmacology*; D018712:Analgesics, Non-Narcotic / Q000494:pharmacology; D000701:Analgesics, Opioid / Q000494:pharmacology; D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)- / Q000494:pharmacology*; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000378:metabolism*; D006153:Guanosine Diphosphate / Q000494:pharmacology; D008252:Macaca fascicularis; D008297:Male; D009270:Naloxone / Q000494:pharmacology; D009928:Organ Specificity; D017473:Receptors, Opioid, kappa / Q000502:physiology*; D017450:Receptors, Opioid, mu / Q000502:physiology*; D013462:Sulfur Radioisotopes
chemical_list: D018712:Analgesics, Non-Narcotic; D000701:Analgesics, Opioid; D017473:Receptors, Opioid, kappa; D017450:Receptors, Opioid, mu; D013462:Sulfur Radioisotopes; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D006153:Guanosine Diphosphate; D009270:Naloxone; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer