A receptor that responds strongly to or is activated by epinephrine and isoproterenol but is relatively unresponsive to levarterenol and that is associated with positive cardiac chronotropic and inotropic effects, vasodilation, and inhibition of smooth muscle in the bronchi, myometrium, and intestine.

β 感官；β 肾上腺素感官(强烈感应或由审上腺素及异丙基肾上腺素激发的感官，与增强心脏变速性及收缩性、血管扩张、仰制气管、子宫层肌及肠等的滑壁有关系)。