9920201

pubmed:Citation

4

CD-1 mice were treated intravenously with streptozotocin, 200 mg/kg, and tested 2 weeks later or treated with 60 mg/kg and tested 3 days later. Both treatments changed the tail flick response of heroin and 6-monoacetylmorphine (6 MAM) given intracerebroventricularly from a mu- to delta-opioid receptor-mediated action as determined by differential effects of opioid receptor antagonists. The response to morphine remained mu. Heroin and 6 MAM responses involved delta1 (inhibited by 7-benzylidenenaltrexone) and delta2 (inhibited by naltriben) receptors, respectively. These delta-agonist actions did not synergize with the mu-agonist action of morphine in the diabetic mice. The expected synergism between the delta agonist, [D-Pen2-D-Pen5]enkephalin (DPDPE), and morphine was not obtained in diabetic mice. Thus, diabetes disrupted the purported mu/delta-coupled response. In nondiabetic CD-1 mice, heroin and 6 MAM produced a different mu-receptor response (not inhibited by naloxonazine) from that of morphine (inhibited by naloxonazine). Also, these mu actions, unlike that of morphine, did not synergize with DPDPE. The unique receptor actions and changes produced by streptozotocin suggest that extrinsic in addition to genetic factors influence the opioid receptor selectivity of heroin and 6 MAM.

eng

IM

MEDLINE

0021-5198

Print

NLM

443-54

pubmed-meshheading:9920201-Analgesics, Opioid, pubmed-meshheading:9920201-Animals, pubmed-meshheading:9920201-Anti-Bacterial Agents, pubmed-meshheading:9920201-Benzylidene Compounds, pubmed-meshheading:9920201-Diabetes Mellitus, Experimental, pubmed-meshheading:9920201-Dose-Response Relationship, Drug, pubmed-meshheading:9920201-Drug Interactions, pubmed-meshheading:9920201-Enkephalin, D-Penicillamine (2,5)-, pubmed-meshheading:9920201-Enkephalins, pubmed-meshheading:9920201-Heroin, pubmed-meshheading:9920201-Injections, Intraventricular, pubmed-meshheading:9920201-Male, pubmed-meshheading:9920201-Mice, pubmed-meshheading:9920201-Morphine, pubmed-meshheading:9920201-Morphine Derivatives, pubmed-meshheading:9920201-Naloxone, pubmed-meshheading:9920201-Naltrexone, pubmed-meshheading:9920201-Narcotic Antagonists, pubmed-meshheading:9920201-Nociceptors, pubmed-meshheading:9920201-Pain, pubmed-meshheading:9920201-Receptors, Opioid, delta, pubmed-meshheading:9920201-Receptors, Opioid, mu, pubmed-meshheading:9920201-Streptozocin, pubmed-meshheading:9920201-Time Factors

Heroin antinociception changed from mu to delta receptor in streptozotocin-treated mice.

Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't