Sympathomimetic Amines, β-Adrenoceptors and Bronchial Asthma

Effects of Terbutaline on α‐Adrenergic Responses and Ca2+ Influx in Isolated Rabbit Aorta

“…In vivo treatment with the P-adrenergic agonist, isoproterenol, does not alter responses of isolated rat aorta and portal vein to u-adrenergic agonists (Hayes et al 1986), although other studies have reported that prolonged exposure of rats (Kazanietz et al 1986) and asthmatics (Conolly 1989) to P-adrenergic agonists increases pressor responses to a-adrenergic agonists in sivo. In vivo treatment with the P-adrenergic agonist, isoproterenol, does not alter responses of isolated rat aorta and portal vein to u-adrenergic agonists (Hayes et al 1986), although other studies have reported that prolonged exposure of rats (Kazanietz et al 1986) and asthmatics (Conolly 1989) to P-adrenergic agonists increases pressor responses to a-adrenergic agonists in sivo.…”

“…Findings on whether or not P-adrenergic agonist administration alters responses of blood vessels to u-adrenergic receptors have varied among investigators. In vivo treatment with the P-adrenergic agonist, isoproterenol, does not alter responses of isolated rat aorta and portal vein to u-adrenergic agonists (Hayes et al 1986), although other studies have reported that prolonged exposure of rats (Kazanietz et al 1986) and asthmatics (Conolly 1989) to P-adrenergic agonists increases pressor responses to a-adrenergic agonists in sivo.…”