G-protein coupling of δ-opioid receptors in brains of μ-opioid receptor knockout mice - Archive ouverte HAL Access content directly
Journal Articles European Journal of Pharmacology Year : 2003

G-protein coupling of δ-opioid receptors in brains of μ-opioid receptor knockout mice

Abstract

Mu-opioid receptor knockout mice have been reported to show loss of some delta-opioid receptor function. We hypothesised that this is due to some delta-opioid receptors being uncoupled from G-proteins in the absence of the mu-opioid receptor. To address this possibility, we have used quantitative autoradiography to determine the binding of three delta-opioid receptor agonist ligands ([3H]deltorphin I, [3H] [R-Atc(3), Ile(5,6)]deltorphin II, [3H] 4-[(alpaR)-alpha-((2S,5R)-4-propyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide (SNC-121)) and the delta-opioid receptor antagonist, [3H]naltrindole in the presence and absence of a GTP analogue, guanylylimidodiphosphate (GMPPNP) in the brains of mice lacking the mu-opioid receptor gene. Guanylylimidodiphosphate caused a decrease in the binding of the agonist ligands (to differing extents) and an increase in binding for the antagonist in wild-type controls. Overall, there were no major differences in the effects of guanylylimidodiphosphate for the agonist ligands in mu-knockout mice although a few structures showed a smaller sensitivity to the effects of this GTP analogue most notably for [3H]naltrindole. These findings suggest that in the majority of brain regions, G-protein coupling is unaltered in mu-opioid receptor knockout mice.

Dates and versions

hal-04154146 , version 1 (06-07-2023)

Identifiers

Cite

Sarah Oakley, Geza Toth, Anna Borsodi, Brigitte Kieffer, Ian Kitchen. G-protein coupling of δ-opioid receptors in brains of μ-opioid receptor knockout mice. European Journal of Pharmacology, 2003, 466 (1-2), pp.91-98. ⟨10.1016/s0014-2999(03)01531-0⟩. ⟨hal-04154146⟩
1 View
0 Download

Altmetric

Share

Gmail Facebook X LinkedIn More