Isoproterenol bitartrate is a beta-sympathomimetic and an isopropyl analog of Epinephrine, which acts on the heart, bronchi, skeletal muscle, and alimentary tract. It is used mainly as a bronchodilator and heart stimulant.
PF-9404C is the S-S diesteroisomer of a beta adrenergic receptors blocker with vasodilatory properties. PF9404C increased the formation of cyclic GMP from 3 pmol mg−1 protein in basal conditions, to 53 pmol mg−1 protein in 10 μM in rat aorta smooth muscle