Terbutaline

Terbutaline is a short-acting β2-adrenergic receptor (β2-AR) agonist and an active metabolite of bambuterol .[1],[2],[3] It binds to β1-, β2-, and β3-ARs (Ki = 31.3, 15.4, and 79.8 nM, respectively) and selectively increases adenylyl cyclase activity in CHO cell membranes expressing recombinant human β2- or β3- over β1-ARs at concentrations 100-fold greater than the respective Ki values.[1] Terbutaline inhibits histamine release induced by ovalbumin in isolated guinea pig lung mast cells.[2] It also inhibits airway obstruction induced by methacholine or leukotriene D4 in anesthetized guinea pigs.[4] Formulations containing terbutaline have been used in the treatment of asthma.

Reference:
[1]. Hoffmann, C., Leitz, M.R., Oberdorf-Maass, S., et al. Comparative pharmacology of human β-adrenergic receptor subtypes - characterization of stably transfected receptors in CHO cells. Naunyn Schmiedebergs Arch. Pharmacol. 369(2), 151-159 (2004).
[2]. Lau, H.Y.A., Wong, P.L., and Lai, C.K.W. Effects of β2-adrenergic agonists on isolated guinea pig lung mast cells. Agents Actions 42(3-4), 92-94 (1994).
[3]. Olsson, O.A.T., and Svenson, L.-•. New lipophilic terbutaline ester prodrugs with long effect duration. Pharm. Res. 1(1), 19-23 (1984).
[4]. Salonen, R.O. Actions of bronchodilator drugs, glucocorticoid, and their combinations on airways in rats and guinea pigs. Acta. Pharmacol. Toxicol. (Copenh) 57(Suppl. 3), 1-38 (1985).