A-77636 hydrochloride is a potent, selective, orally active and long acting dopamine D1 receptor agonist with Ki of 39.8 nM. A-77636 is an agonist at the dopamine D1 receptors in the fish retina with EC50 of 1.1 nM. A-77636 is functionally inactive at dopamine D2 receptors (EC50>10 uM). A-77636 increases locomotor activity and decreases the severity of the parkinsonian-like symptoms in marmosets treated with MPTP to induce a parkinsonian-like state in rats and mice.
