Ethyldibunate, Benzonatateおよび(-)-Methylephedrineの鎮咳効果の作用点について

抄録

The antitussive activities and site of antitussive actions of Ethyldibunate, Benzonatate, and (-)-methylephedrine have been investigated. The antitussive activities of the test drugs, evaluated by the "coughing dog and cat" methods, were as follows : Ethyldibunate, 13% and 9% that of codeine in dogs and cats, respectively ; Benzonatate, 80%, 56% ; (-)-methylephedrine, 38.31%. The antitussive actions of Ethyldibunate and (-)-methylephedrine are due to depression of the cough center, while that of benzonatate seems to be at the pulmonary stretch receptor. This conclusion was derived from the analyses of their actions by the following tests : Comparison of equi-active doses in four different routes of administration, effects on the sensory nerve endings in the trachea and on the pulmonary stretch receptor impulses, the influence of decerebration by mid-collicular transection, effects on the central1y-induced cough response and on the centrally-induced sustained inspiratory response, effects on the centrifugal respiratory pathways.