title: Interaction of Ca++ with normorphine and beta-endorphin on the guinea pig ileum.
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D004347:Drug Interactions; D004723:Endorphins / Q000494:pharmacology*; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects*; D066298:In Vitro Techniques; D009022:Morphine Derivatives / Q000494:pharmacology*; D009119:Muscle Contraction / Q000187:drug effects; D009619:Nociceptors / Q000187:drug effects; D001615:beta-Endorphin
chemical_list: D004723:Endorphins; D009022:Morphine Derivatives; D001615:beta-Endorphin; D000109:Acetylcholine; D002118:Calcium; C010616:normorphine