Regulation of the Neuroblastoma X Glioma Hybrid Opiate Receptors by Na+ and Guanine Nucleotides

Blume, Arthur J.; Boone, Gloria; Lichtshtein, David

doi:10.1007/978-1-4684-3503-0_9

Cited by 20 publications

(9 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The question arises as to whether or not the requirement for Na+ is related to the known Na+ regulation of NG108-15 opiate receptors (4,5). As reported (5), AMEA binding affinity is selectively decreased by monovalent cations with a potency order of Na+ > Li+ > K > choline+ and with an apparent Km for Na+ of z20 mM.…”

Section: Methodsmentioning

confidence: 89%

“…Investigation of the specificity of action of nucleotide triphosphates in this phenomenon revealed that ITP, but not UTP, CTP, or ATP, could replace GTP (Table 4). Our earlier studies on opiate binding to NG108-15 receptors showed that GDP also regulates these opiate receptors (4,5). The possible effectiveness of GDP as a coupler could not be ascertained because a nucleotide triphosphate-regenerating system is present in the adenylate cyclase assay mixtures in order to maintain constant substrate levels of ATP.…”

Section: I-~20mentioning

confidence: 99%

“…This regulation of cAMP requires occupation of highly specific receptors by opiate agonists and is blocked by opiate antagonists. Recently, these opiate receptors were found to be sensitive to guanine nucleotides (4,5) and Na+ (4)(5)(6)(7). The effects of Na+ and nucleotides on NG108-15 opiate receptors parallel the effects of Na+ (8)(9)(10)(11)(12)(13)(14) and nucleotides (15,16) on brain opiate receptors.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Coupling of opiate receptors to adenylate cyclase: requirement for Na+ and GTP.

Blume¹,

Lichtshtein²,

Boone³

1979

Proc. Natl. Acad. Sci. U.S.A.

166

View full text Add to dashboard Cite

Inhibition of the adenylate cyclase activity in homogenates of mouse neuroblastoma-glioma hybrid cells (NG108-15) by the opioid peptide [-Ala2,Metsjenkephalin amide (AMEA) requires the presence of Na+ and GTP. In this process, the selectivity for monovalent cations is Na+ > Li+ > K+ > choline+; ITP will replace GTP but ATP, UTP, or CTP will not. The apparent Km for Na+ is 20 mM and for GTP it is I .&M. Under saturating Na+ and GTP conditions, the apparent Ki for AMEA-directed inhibition is 20 nM for basal and 100 nM for prostaglandin E1-activated adenylate cyclase activity. For both cyclase activities, maximal inhibition is only partial (i.e., -55% of control in each case). In intact viable NG108-15 cells, the decrease in basal and prostaglandin El-stimulated intracellular cyclic AMP concentrations by AMEA is also dependent upon extracellular Na+. Thee ephalin-directed reductions in cyclic AMP co riss are at least 75%. The specificity of the monovalent cation requirement for enkephalin action on intact cells is the same as for enkephalin regulation of homogenate adenylate cyclase activity. Based on these data, a model is presented in which the transfer of information from opiate receptors to adenylate cyclase requires active separate membrane components, which correspond to the sites of action of Na+ and GTP in this process. Opiates decrease the intracellular cyclic AMP (cAMP) concentrations of intact mouse neuroblastoma-rat glioma hybrid cells (NG108-15) by inhibiting the activity of the adenylate cyclase of these cells (1-3). This regulation of cAMP requires occupation of highly specific receptors by opiate agonists and is blocked by opiate antagonists. Recently, these opiate receptors were found to be sensitive to guanine nucleotides (4, 5) and Na+ (4-7). The effects of Na+ and nucleotides on NG108-15 opiate receptors parallel the effects of Na+ (8-14) and nucleotides (15, 16) on brain opiate receptors. Although nucleotides and Na+ have nonspecific effects on NG108-15 and brain opiate receptors, the actions of ions and nucleotides can be used to discriminate between agonist and antagonist interactions with opiate receptors.The selective nucleotide and ion regulation of agonist interactions with opiate receptors is reminiscent of the welldocumented guanine nucleotide regulation of agonist interaction with hormonal receptors that mediate activations of adenylate cyclase (17-20). In the latter case, agonist occupation of the receptor can take place without any nucleotides present; however, in order for the agonist-receptor complex to cause an increase in adenylate cyclase activity, the presence of a guanine nucleotide is required. Biochemical (21), genetic (22, 23), cell fusion (24, 25), and reconstitution (26-37) studies have shown that the receptor and catalytic units of adenylate cyclase are separate proteins and that another membrane component(s) (here termed the "coupler") is actually required for receptordirected activation of the catalytic unit.The published observations of Na+ and nucleotide sen...

show abstract

Section: Methodsmentioning

confidence: 89%

Section: I-~20mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Coupling of opiate receptors to adenylate cyclase: requirement for Na+ and GTP.

Blume¹,

Lichtshtein²,

Boone³

1979

Proc. Natl. Acad. Sci. U.S.A.

166

View full text Add to dashboard Cite

show abstract

“…In NG108-15, opiate agonists (both alkaloids and peptides) regulate the activity of at least two enzymes located within the cell's plasma membrane: adenylate cyclase (Sharma et al, 1975) and a GTPase (Koski and Klee, 1981). Sodium and guanine nucleotides are required, in vitro, for these two opiate sequelas (Blume et al, 1979a;Koski and Klee, 1981) and both agents modify the binding of opiate agonists to their receptors (Blume, 1978;Blume et al, 197913).…”

mentioning

confidence: 99%

“…Most likely an association exists between the NG108-15 opiate receptor and a nucleotide-binding protein. With great specificity, guanine nucleotides clearly modify opiate agonist binding to NGlOB-15 receptors (Blume, 1978;Blume et al, 1979a). In addition, the alkylation of a single --SH group outside of the opiate ligand-binding domain causes both a loss in agonist affinity and a loss in nucleotide sensitivity.…”

mentioning

confidence: 99%

Protection of opiate receptors in NG108-15 against modification by N- ethylmaleimide

Mullikin‐Kilpatrick¹,

Ne²,

Aj³

1983

J. Neurosci.

View full text Add to dashboard Cite

Two different -SH groups associated with the opiate receptors of the mouse neuroblastoma X rat glioma hybrid NG108-15 have been identified. Modification of these by N-ethylmaleimide (NEM) (presumed to be via alkylation) or by para-chloromercuribenzoic acid (presumed to be via formation of mercury adducts) decreases the binding of both opiate agonists and antagonists to these receptors. Agonist binding is more sensitive than antagonist binding to modification by NEM. Losses in antagonist binding are accounted for totally by decreases in the number of binding sites; there are no corresponding losses in antagonist affinity. Losses of antagonist binding exhibit a pseudo-first order rate constant; the modification of only one such group completely destroys the binding site. Both agonists and antagonists protect against modification of this group by NEM. Sodium and lithium, but not GTP, also protect this group, indicating that the action of these monovalent cations is directly on the receptor moiety. Losses in agonist binding stem not only from decreases in receptor number but also from selective losses in affinity. This -SH group appears to be different from the one at the binding site as sodium, GTP, and antagonist ligands do not protect against losses in agonist affinity. Agonist high affinity also is lost in a pseudo-first order fashion indicating that an alteration of only one -SH group per receptor complex is sufficient to produce this effect. The possible roles of two sulfhydryls in opiate receptor function are discussed.

show abstract

Opioid peptide receptor studies. 10. Nor-BNI differentially inhibits kappa receptor agonist-induced G-protein activation in the guinea pig caudate: Further evidence of kappa receptor heterogeneity

Heyliger¹,

Jackson²,

Rice³

et al. 1999

Synapse

View full text Add to dashboard Cite

There is strong evidence supporting the existence of multiple kappa receptors. Previous studies proposed that U69,593 and (+)-tifluadom act on different kappa receptor subtypes, kappa(1) (kappa(1)) and kappa(2) (kappa(2)), respectively. In this study, we investigated the effects of the kappa selective antagonist nor-binaltorphimine (Nor-BNI) on U69,593- and (+)-tifluadom-induced receptor-mediated stimulation of [(35)S]-GTP-gamma-S binding in the guinea pig caudate. The IC(50) value of Nor-BNI in the presence of a stimulating concentration of U69,593 (1 microM) was 0.19+/-0.02; while the IC(50) for Nor-BNI in the presence of (+)-tifluadom (1 microM) was 13.9+/- 1.62 nM. The mu-opioid receptor antagonist CTAP (10,000 nM) significantly reduced (+)-tifluadom-stimulated [(35)S]-GTP-gamma-S binding in rat brain sections and guinea pig brain membranes, indicating that (+)-tifluadom has mu agonist activity. Under conditions in which the mu agonist activity of (+)-tifluadom was blocked by 1000 nM CTAP the Ki value for Nor-BNI for inhibition of U69,593-stimulated [(35)S]-GTP-gamma-S binding was 0.036+/-.004 nM, whereas, its Ki value for the (+)-tifluadom-stimulated [(35)S]-GTP-gamma-S binding was 0.27+/-.015 nM. These results suggest that (+)-tifluadom and U69,593 activate pharmacologically different receptors. This study provides functional evidence in support of kappa receptor heterogeneity.

show abstract

Regulation of the Neuroblastoma X Glioma Hybrid Opiate Receptors by Na+ and Guanine Nucleotides

Cited by 20 publications

References 13 publications

Coupling of opiate receptors to adenylate cyclase: requirement for Na+ and GTP.

Coupling of opiate receptors to adenylate cyclase: requirement for Na+ and GTP.

Protection of opiate receptors in NG108-15 against modification by N- ethylmaleimide

Opioid peptide receptor studies. 10. Nor-BNI differentially inhibits kappa receptor agonist-induced G-protein activation in the guinea pig caudate: Further evidence of kappa receptor heterogeneity

Contact Info

Product

Resources

About