@article {Wasserman445, author = {Martin A. Wasserman and Bernard Levy}, title = {CARDIOVASCULAR AND BRONCHOMOTOR RESPONSES TO SELECTIVE BETA ADRENERGIC RECEPTOR AGONISTS IN THE ANESTHETIZED DOG}, volume = {189}, number = {2}, pages = {445--455}, year = {1974}, publisher = {American Society for Pharmacology and Experimental Therapeutics}, abstract = {This investigation compared the selectivity of the beta adrenergic receptor agonists, salbutamol and terbutaline, with the relative nonselectivity of isoproterenol on cardiac, vascular and bronchiolar responses in anesthetized dogs. Dose-response data were obtained and the geometric mean ED values and relative potency ratios were calculated. From these data, the relative order of agonist potency appears to be: isoproterenol \> salbutamol \> terbutaline. Whereas isoproterenol was a potent activator of all beta receptors, salbutamol and terbutaline were relatively more potent activators of pulmonary and vascular beta receptors than of cardiac beta receptors. For reducing histamine-induced bronchospasm salbutamol was {\textonehalf} as potent and terbutaline was 1/6 as potent as isoprotenenol. For vascular responses salbutamol was 1/20 and terbutaline was 1/30 to 1/20 as active as isoproterenol. For cardiac rate and force, both salbutamol and terbutaline produced dose-response curves that were less steep than those for isoproterenol and that did not approach the same maximum level produced by isoproterenol. A comparison of the interactions of the three agents on the receptors studied suggests the existence of three different beta adrenergic receptor subtypes in the dog: one in cardiac, another in vascular and a third in bronchiolar muscle. {\textcopyright} 1974 by The Williams \& Wilkins Co.}, issn = {0022-3565}, URL = {https://jpet.aspetjournals.org/content/189/2/445}, eprint = {https://jpet.aspetjournals.org/content/189/2/445.full.pdf}, journal = {Journal of Pharmacology and Experimental Therapeutics} }