title: Effect of drug-induced tone on the ability of histamine H2 receptor agonists to relax guinea-pig tracheal chain.
mesh_terms: D000818:Animals; D017259:Dimaprit; D006146:Guanidines / Q000494:pharmacology; D006168:Guinea Pigs; D007093:Imidazoles / Q000494:pharmacology; D017446:Impromidine; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009126:Muscle Relaxation / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D011968:Receptors, Histamine / Q000502:physiology*; D011970:Receptors, Histamine H2 / Q000502:physiology*; D013890:Thiourea / Q000494:pharmacology; D014132:Trachea / Q000187:drug effects
chemical_list: D006146:Guanidines; D007093:Imidazoles; D011968:Receptors, Histamine; D011970:Receptors, Histamine H2; D017446:Impromidine; D013890:Thiourea; D007545:Isoproterenol; D017259:Dimaprit