Evidence for opioid receptor-mediated activation of the G-proteins, Go and Gi2, in membranes of neuroblastoma x glioma (NG108-15) hybrid cells.

Abstract

In membranes of neuroblastoma x glioma (NG108-15) hybrid cells, the photoreactive GTP analog, [alpha-32P] GTP azidoanilide, was incorporated into 39-41-kDa proteins comigrating in urea-containing sodium dodecyl sulfate-polyacrylamide gels with immunologically identified G-protein alpha-subunits, i.e. a 39-kDa Go alpha-subunit, a 40-kDa Gi2 alpha-subunit, and a 41-kDa Gi alpha-subunit of an unknown subtype. The synthetic opioid, D-Ala2,D-Leu5-enkephalin (DADLE), stimulated photolabeling of the 39-41-kDa proteins. In the presence of GDP, which increased the ratio of agonist-stimulated to basal photolabeling, DADLE at a maximally effective concentration stimulated photolabeling of the 39- and the 40-kDa protein 2-3-fold. Somatostatin, adrenaline, and bradykinin were less potent than DADLE and, to varying degrees, stimulated photolabeling of the 40-kDa protein more than that of the 39-kDa protein. Prostaglandin E1 was inactive. The present data represent direct evidence for an activation of endogenous Go and Gi2 via opioid receptors and other receptors in the native membrane milieu.

• Authors: S Offermanns, G Schultz, W Rosenthal
• Journal: The Journal of biological chemistry (J Biol Chem) Vol. 266 Issue 6 Pg. 3365-8 (Feb 25 1991) ISSN: 0021-9258 [Print] United States
• PMID: 1671672 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Carrier Proteins
• Cell Adhesion Molecules
• Membrane Glycoproteins
• Naloxone
• Somatostatin
• Enkephalin, Leucine-2-Alanine
• GTP-Binding Proteins
• Alprostadil
• Bradykinin
• Epinephrine

Topics

• Alprostadil (pharmacology)
• Bradykinin (pharmacology)
• Carrier Proteins (drug effects, metabolism)
• Cell Adhesion Molecules
• Electrophoresis, Polyacrylamide Gel
• Enkephalin, Leucine-2-Alanine (pharmacology)
• Epinephrine (pharmacology)
• GTP-Binding Proteins (metabolism)
• Glioma (metabolism)
• Hybrid Cells
• Membrane Glycoproteins (drug effects, metabolism)
• Naloxone (pharmacology)
• Neuroblastoma (metabolism)
• Somatostatin (pharmacology)
• Tumor Cells, Cultured (metabolism)