[Effects of d-pseudoephedrine on tracheo-bronchial muscle and the cardiovascular system (author's transl)].
The action of d-psuedoephedrine on bronchial smooth muscle, respiratory resistance and blood pressure was compared with that of 1-ephedrine. The following results were obtained. 1) Administration of dl-isoproterenol on isolated guinea pig tracheal muscle previously constricted with acetylcholine (ACh) or histamine (his) was the most effective and d-pseudoephedrine had the same effect as 1-ephedrine. The relaxing effect of dl-isoproterenol, 1-ephedrine or d-pseudoephedrine on ACh or His induced tracheal constriction was competitively antagonized by the pretreatment of propranolol. 2) The intravenous or sublingual administration of d-pseudoephedrine on the increased respiratory resistance induced by His produced the same effect as 1-ephedrine. 3) The increase in blood pressure with d-pseudoephedrine was weaker than that of 1-ephedrine. 4) When 1-ephedrine of d-pseudoephedrine was repeatedly injected into the same animal, signs of tachyphylaxis were observed. It was found that d-pseudoephedrine, the main alkaloid of Ephedrine Helba, exhibited the relaxing effect on bronchial smooth muscles as did 1-ephedrine. The respiratory resistance increased by His was inhibited by the sublingual administration of d-pseudoephedrine and 1-ephedrine.
D000284:Administration, Oral; D000403:Airway Resistance / Q000187:drug effects; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002319:Cardiovascular System / Q000187:drug effects*; D004285:Dogs; D004809:Ephedrine / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D006168:Guinea Pigs; D066298:In Vitro Techniques; D007275:Injections, Intravenous; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D013237:Stereoisomerism; D014132:Trachea / Q000187:drug effects*
D004809:Ephedrine