Effects of the selective delta opioid agonist SNC80 on cocaine- and food-maintained responding in rhesus monkeys.

Abstract

Delta agonists such as SNC80 ((+)-4-[(aR)-a-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide) produce some cocaine-like behavioral effects and warrant evaluation as candidate "agonist" medications for cocaine abuse. The present study examined acute and chronic effects of the systemically active delta agonist SNC80 on cocaine- and food-maintained responding in rhesus monkeys. Acute SNC80 (0.32-3.2 mg/kg, i.m.) pretreatment dose-dependently decreased cocaine self-administration (0.0032 mg/kg/injection), but doses of SNC80 that decreased cocaine self-administration also decreased food-maintained responding. In chronic studies, SNC80 (0.32-3.2 mg/kg/h, i.v.) was delivered for 7 days, and food or cocaine (0.01 mg/kg/injection) was available during 4 daily components of food availability and 4 daily components of drug availability. Chronic SNC80 (1.8 mg/kg/h) tended to decrease cocaine self-administration but produced greater reductions in food-maintained responding. A higher dose of 3.2 mg/kg/h SNC80 eliminated both cocaine- and food-maintained responding and produced profound sedation in one monkey and was not tested in other monkeys. These findings indicate that SNC80 produced dose-dependent and non-selective reductions in cocaine self-administration. These results suggest that SNC80 is unlikely to be useful as a treatment for cocaine dependence.

• Authors: Gail Pereira Do Carmo, Nancy K Mello, Kenner C Rice, John E Folk, S Stevens Negus
• Journal: European journal of pharmacology (Eur J Pharmacol) Vol. 547 Issue 1-3 Pg. 92-100 (Oct 10 2006) ISSN: 0014-2999 [Print] Netherlands
• PMID: 16934797 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, N.I.H., Intramural)

Chemical References

• Benzamides
• Piperazines
• Receptors, Opioid, delta
• 4-(alpha-(4-allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl)-N,N-diethylbenzamide
• Cocaine

Topics

• Analysis of Variance
• Animals
• Behavior, Animal (drug effects)
• Benzamides (pharmacology)
• Cocaine (administration & dosage)
• Cocaine-Related Disorders (physiopathology, prevention & control, psychology)
• Conditioning, Operant (drug effects)
• Dose-Response Relationship, Drug
• Female
• Food
• Macaca mulatta
• Male
• Piperazines (pharmacology)
• Receptors, Opioid, delta (agonists)
• Reinforcement Schedule
• Self Administration
• Time Factors