title: The effect of trans-4-guanidinomethylcyclohexanecarboxylic acid p-tert-butylphenyl ester hydrochloride (NCO-650) on Ascaris suum antigen-induced bronchoconstriction in dogs.
abstract: Antiallergic asthma effect of trans-4-guanidinomethylcyclohexane-carboxylic acid p-tert-butylphenyl ester hydrochloride (NCO-650), a new anti-allergic drug, was investigated in comparison with those of tranilast and disodium cromoglycate (DSCG) in anesthetized dogs. The asthmatic bronchoconstriction was induced by inhalation of Ascaris suum antigen (Asc-Ag) to naturally Ascaris-sensitive dogs. The airway resistance was determined using the modified Konzett-Rössler method. Both intravenous (1 and 5 mg/kg) and intraduodenal (10, 30 and 100 mg/kg) administrations of NCO-650 prior to the antigen challenge markedly inhibited the asthmatic bronchoconstriction induced by Asc-Ag inhalation. The antiasthmatic effect of NCO-650 was much stronger than that of DSCG (10 mg/kg, i.v.) and was about three-fold stronger than that of tranilast. On the other hand, when NCO-650 was administered after the antigen challenge, the agent had no inhibitory effect on the Asc-Ag induced bronchoconstriction. As for the effects on increased airway secretion at the time of asthmatic attack, NCO-650 inhibited the excessive secretions without any remarkable change in the viscosity of the secretions. NCO-650 had no effect on the bronchoconstriction induced by inhalation of acetylcholine, suggesting that NCO-650 appears to have no anti-cholinergic effect and thus no effect on the vagal reflex that occurred during the asthmatic responses. The above findings show that NCO-650 may be useful for the treatment of bronchial asthma as an orally active drug.
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D000947:Antigens, Helminth / Q000276:immunology; D001200:Ascaris / Q000276:immunology; D001249:Asthma / Q000209:etiology / Q000517:prevention & control*; D001980:Bronchi / Q000187:drug effects*; D004205:Cromolyn Sodium / Q000494:pharmacology; D003509:Cyclohexanecarboxylic Acids / Q000494:pharmacology*; D004285:Dogs; D006969:Hypersensitivity, Immediate; D008297:Male; D011480:Protease Inhibitors / Q000494:pharmacology*; D012882:Skin Tests; D062367:ortho-Aminobenzoates / Q000494:pharmacology
chemical_list: D000947:Antigens, Helminth; D003509:Cyclohexanecarboxylic Acids; D011480:Protease Inhibitors; D062367:ortho-Aminobenzoates; C038303:NCO 650; C012293:tranilast; D000109:Acetylcholine; D004205:Cromolyn Sodium