[Effects of newly isolated opioid peptides on G-protein activation: usefulness of [35S] GTP gamma S binding study and its practical application]
- PMID: 9866825
[Effects of newly isolated opioid peptides on G-protein activation: usefulness of [35S] GTP gamma S binding study and its practical application]
Abstract
Recent cloning and expression studies have revealed that the opioid mu-, delta-, kappa- and orphan receptors are seven-transmembrane domain receptors whose actions are mediated through activation of guanine nucleotide binding protein (G-protein). The activation of G-proteins by the opioid receptor can be measured by assessing agonist stimulation of membrane binding of the non-hydrolyzable analog of guanosine triphosphate (GTP), guanosine-5'-O-(3-[35S] thio) triphosphate ([35S] GTP gamma S). Our recent data suggest that 1) the level of spinal mu-, delta-, kappa- and orphan-receptor agonist-stimulated [35S] GTP gamma S binding closely parallels that of receptor binding densities, 2) the neuroanatomical distribution of opioid agonist-stimulated [35S] GTP gamma S binding relates to receptor binding distribution, 3) newly isolated opioid peptides, endomorphin-1 and -2, can activate G-proteins by specific stimulation of mu-receptors and act as partial agonists with moderate catalytic efficacies, 4) mu-receptor densities could be rate-limiting steps in the G-protein activation by mu-agonists in the spinal cord region. In conclusion, opioid agonist-stimulated [35S] GTP gamma S binding can provide a functional method to localize receptors not only by their ability to bind ligands, but also according to their ability to activate an intracellular signal transducer.
Similar articles
-
Modulation by mu-opioid agonists of guanosine-5'-O-(3-[35S]thio)triphosphate binding to membranes from human neuroblastoma SH-SY5Y cells.Mol Pharmacol. 1995 Apr;47(4):848-54. Mol Pharmacol. 1995. PMID: 7723747
-
Absence of G-protein activation by mu-opioid receptor agonists in the spinal cord of mu-opioid receptor knockout mice.Br J Pharmacol. 1999 Jan;126(2):451-6. doi: 10.1038/sj.bjp.0702330. Br J Pharmacol. 1999. PMID: 10077238 Free PMC article.
-
Signal transduction correlates of mu opioid agonist intrinsic efficacy: receptor-stimulated [35S]GTP gamma S binding in mMOR-CHO cells and rat thalamus.J Pharmacol Exp Ther. 1998 May;285(2):496-505. J Pharmacol Exp Ther. 1998. PMID: 9580589
-
Differential mechanism of G-protein activation induced by endogenous mu-opioid peptides, endomorphin and beta-endorphin.Jpn J Pharmacol. 2002 Jul;89(3):229-34. doi: 10.1254/jjp.89.229. Jpn J Pharmacol. 2002. PMID: 12184727 Review.
-
Assay of G protein-coupled receptor activation of G proteins in native cell membranes using [35S]GTP gamma S binding.Methods Mol Biol. 2004;237:135-43. doi: 10.1385/1-59259-430-1:135. Methods Mol Biol. 2004. PMID: 14501046 Review.
Publication types
MeSH terms
Substances
LinkOut - more resources
Research Materials