L-Phenylephrine-(hydro-chloride)

L-Phenylephrine is an adrenergic α1A receptor agonist (Ki = 1.4 µM) that demonstrates selectivity against the α1B and α1C receptor subtypes (Kis = 23.9 and 47.8 µM, respectively). By stimulating adrenergic α1 receptors, L-phenylephrine can induce aortic smooth muscle contractions, although reported relative affinity and potency values in rabbit are 5-fold weaker compared to that of L-norepinephrine (Item No. 16673). This compound is frequently used to precontract smooth muscle in preparations designed to study the properties of various vasodilator agents.