Behavioural and biochemical effects in C57BL/6J mice after a prolonged treatment with the delta-opiate antagonist ICI 154129.
A long term treatment with the delta-selective opiate antagonist NN-bisallyl-Tyr-Gly-Gly-psi-(CH2S)-Phe-Leu-OH (ICI 154129) produces an increase in the number of delta-opiate binding sites, whereas the same treatment with the non selective opiate antagonist naloxone results in an enhancement of both mu- and delta-binding sites. This biochemical effect in naloxone-pretreated mice is paralleled by a more pronounced increase in locomotor activity induced by a challenge dose of morphine. In contrast, no difference in the effect of morphine was seen in ICI 154129-pretreated mice with respect to control. These data suggest that the locomotor response to morphine in C57 mice is not mediated through delta-opiate receptors.
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D001923:Brain Chemistry / Q000187:drug effects*; D001933:Brain Stem / Q000378:metabolism; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives* / Q000494:pharmacology; D016308:Enkephalin, Leucine-2-Alanine; D007981:Levorphanol / Q000494:pharmacology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009043:Motor Activity / Q000187:drug effects; D009270:Naloxone / Q000494:pharmacology; D011957:Receptors, Opioid / Q000187:drug effects* / Q000378:metabolism; D017465:Receptors, Opioid, delta
D000317:Adrenergic alpha-Antagonists; D011957:Receptors, Opioid; D017465:Receptors, Opioid, delta; D007981:Levorphanol; D009270:Naloxone; D004743:Enkephalin, Leucine; D016308:Enkephalin, Leucine-2-Alanine; C036405:ICI 154129