guanosine-diphosphate and Substance-Withdrawal-Syndrome

guanosine-diphosphate has been researched along with Substance-Withdrawal-Syndrome* in 1 studies

Other Studies

1 other study(ies) available for guanosine-diphosphate and Substance-Withdrawal-Syndrome

Article	Year
Long-term adaptation to high doses of morphine causes desensitization of mu-OR- and delta-OR-stimulated G-protein response in forebrain cortex but does not decrease the amount of G-protein alpha subunits. Medical science monitor : international medical journal of experimental and clinical research, 2010, Volume: 16, Issue:8 The functional activity of trimeric guanine-nucleotide-binding proteins (G-proteins) represents an essential step in linking and regulation of the opioid receptor (mu-, delta- and kappa-OR)-initiated signaling pathways. Theoretical basis and/or molecular mechanism(s) of opioid tolerance and addiction proceeding in the central nervous system were not studied in the forebrain cortex of mammals with respect to quantitative analysis of opioid-stimulated trimeric G-protein activity.. G-protein activity was measured in PercollR-purified plasma membranes (PM) isolated from the frontal brain cortex of control and morphine-treated rats by both high-affinity [32P]GTPase and [35S]GTPgammaS binding assays. Exposition to morphine was performed by intra-muscular application of this drug. Control animals were injected with sterile PBS.. Both mu-OR (DAMGO)- and delta-OR (DADLE)-responses were clearly desensitized in PM isolated from morphine-treated rats; kappa-OR (U-69593)- and baclofen (GABAB-R)-stimulated [35S]GTPgammaS binding was unchanged, indicating the specificity of the morphine effect. Under such conditions, the amount of G-protein alpha subunits was unchanged. The order of efficacy DADLE>DAMGO>U-69593 was the same in control and morphine-treated PM. Behavioral tests indicated that morphine-treated animals were fully drug-dependent and developed tolerance to subsequent drug addition.. Prolonged exposure of rats to high doses of morphine results in decrease of the over-all output of OR-stimulated G-protein activity in the forebrain cortex but does not decrease the amount of these regulatory proteins. These data support the view that the mechanism of the long-term adaptation to high doses of morphine is primarily based on desensitization of OR-response preferentially oriented to mu-OR and delta-OR. Topics: Adaptation, Physiological; Animals; Baclofen; Behavior, Animal; Cell Membrane; Cerebral Cortex; Dose-Response Relationship, Drug; Drug Tolerance; Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; GTP-Binding Protein alpha Subunits; Guanosine 5'-O-(3-Thiotriphosphate); Guanosine Diphosphate; Male; Morphine; Rats; Rats, Wistar; Receptors, Opioid, delta; Receptors, Opioid, mu; Substance Withdrawal Syndrome; Time Factors	2010

Article

Year

Long-term adaptation to high doses of morphine causes desensitization of mu-OR- and delta-OR-stimulated G-protein response in forebrain cortex but does not decrease the amount of G-protein alpha subunits.

Medical science monitor : international medical journal of experimental and clinical research, 2010, Volume: 16, Issue:8

The functional activity of trimeric guanine-nucleotide-binding proteins (G-proteins) represents an essential step in linking and regulation of the opioid receptor (mu-, delta- and kappa-OR)-initiated signaling pathways. Theoretical basis and/or molecular mechanism(s) of opioid tolerance and addiction proceeding in the central nervous system were not studied in the forebrain cortex of mammals with respect to quantitative analysis of opioid-stimulated trimeric G-protein activity.. G-protein activity was measured in PercollR-purified plasma membranes (PM) isolated from the frontal brain cortex of control and morphine-treated rats by both high-affinity [32P]GTPase and [35S]GTPgammaS binding assays. Exposition to morphine was performed by intra-muscular application of this drug. Control animals were injected with sterile PBS.. Both mu-OR (DAMGO)- and delta-OR (DADLE)-responses were clearly desensitized in PM isolated from morphine-treated rats; kappa-OR (U-69593)- and baclofen (GABAB-R)-stimulated [35S]GTPgammaS binding was unchanged, indicating the specificity of the morphine effect. Under such conditions, the amount of G-protein alpha subunits was unchanged. The order of efficacy DADLE>DAMGO>U-69593 was the same in control and morphine-treated PM. Behavioral tests indicated that morphine-treated animals were fully drug-dependent and developed tolerance to subsequent drug addition.. Prolonged exposure of rats to high doses of morphine results in decrease of the over-all output of OR-stimulated G-protein activity in the forebrain cortex but does not decrease the amount of these regulatory proteins. These data support the view that the mechanism of the long-term adaptation to high doses of morphine is primarily based on desensitization of OR-response preferentially oriented to mu-OR and delta-OR.

Topics: Adaptation, Physiological; Animals; Baclofen; Behavior, Animal; Cell Membrane; Cerebral Cortex; Dose-Response Relationship, Drug; Drug Tolerance; Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; GTP-Binding Protein alpha Subunits; Guanosine 5'-O-(3-Thiotriphosphate); Guanosine Diphosphate; Male; Morphine; Rats; Rats, Wistar; Receptors, Opioid, delta; Receptors, Opioid, mu; Substance Withdrawal Syndrome; Time Factors

2010