Involvement of delta- and mu-opioid receptors
in the potentiation of brain-stimulation reward

Duvauchelle CL, Fleming SM, Kornetsky C
Boston University School of Medicine,
Laboratory of Behavioral Pharmacology,
MA 02118, USA.
Eur J Pharmacol 1996 Dec 5; 316(2-3):137-43


A rate-free method of determining brain-stimulation reward thresholds was used to identify the rewarding effects of the delta-opioid receptor and mu-opioid receptor agonist peptides, [D-Pen2, D-Pen5]enkephalin (DPDPE) and [D-Ala2-MePhe4-Gly(o1)5]enkephalin (DAMGO). The nucleus accumbens-delivered opioid receptor agonists produced marked lowering of the threshold for ventral tegmental area brain-stimulation reward. No change in baseline thresholds was seen after peripheral administration of the nonpeptide delta-opioid receptor antagonist, naltrindole. However, an unexpected finding was that naltrindole blocked the threshold-lowering effects of both DPDPE and DAMGO. These data demonstrate nucleus accumbens activation of delta- and mu-opioid receptors and ventral tegmental area brain-stimulation reward share common brain substrates. In addition, the interference of both delta- and mu-opioid receptor mediated reward by naltrindole may have implications for therapeutic use.
Delta agonists
The delta connection
Fentanyl and ketamine
Mu, delta, kappa and emotion
Kappa upregulation and addiction
Delta-opioid receptor agonists as antidepressants?
Chronic morphine induces emergence of functional delta-opioid receptors

and further reading

Future Opioids
BLTC Research
Utopian Surgery?
The Abolitionist Project
The Hedonistic Imperative
The Reproductive Revolution
Critique of Huxley's Brave New World

The Good Drug Guide
The Good Drug Guide

The Responsible Parent's Guide
To Healthy Mood Boosters For All The Family