Cross-tolerance between ethanol and morphine in the guinea-pig ileum longitudinal-muscle/myenteric-plexus preparation.
Morphinization of guinea pigs with s.c. implanted pellets (4 X 75 mg morphine base) has resulted in tolerance, within the isolated longitudinal muscle/myenteric plexus preparation, to the in vitro inhibitory effects of morphine on the electrically induced contractions, and in cross-tolerance to the inhibitory effects of ethanol. Similar results were observed with opiate-naive preparations that were incubated for 18 h in Krebs-Ringer solution containing 40 muM morphine. Daily ethanol injections (6 g/kg) resulted in tolerance to ethanol and cross-tolerance to morphine. These results suggest a commonality between ethanol and morphine actions on the myenteric plexus preparation.
D000818:Animals; D002118:Calcium / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004361:Drug Tolerance; D000431:Ethanol / Q000494:pharmacology*; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D008954:Models, Biological; D009020:Morphine / Q000494:pharmacology*; D009119:Muscle Contraction / Q000187:drug effects*; D009197:Myenteric Plexus / Q000187:drug effects*; D009469:Neuromuscular Junction / Q000187:drug effects*
D000431:Ethanol; D009020:Morphine; D002118:Calcium