LY 171859

LY 171859 is a D2 receptor agonist with significant reductase activity. LY 171859 exhibits enzymatic activity in the cytoplasm of liver, lung, and kidney, and also contains significant reductase activity in rat and human blood. LY 171859 has higher hepatic reductase activity in guinea pigs, followed by hamsters, rabbits, rats, and mice. The substrate of LY 171859 shows an apparent Km of 5.6 μM. The reduction reaction of LY 171859 is NADPH-dependent with an apparent Km of 14.8 μM. Only the A-side hydrogen of NADPH is incorporated in the reduction product of LY 171859. The reaction of LY 171859 is inhibited by cyanide and thiol reagents, and phenobarbital does not induce its activity in rats[1].