Y-27632 dihydrochloride is a selective Rho-kinase inhibitor, which suppresses cholinergic nerve-mediated contractions. In addition, studies show that Y-27632 dihydrochloride increases the release of neurotransmitters from cholinergic nerves. Studies conducted on smooth muscle preparations suggest that Y-27632 dihydrochloride suppresses nerve-mediated contractile responses stimulated by acetylcholine and noradrenaline. Furthermore, studies on lung tissue damage in rats suggest that Y-27632 dihydrochloride can restore the damage caused by oleic acid by inhibition of ROCK-1 and ROCK-2. Y-27632 dihydrochloride also inhibits protein kinase C related kinase, PRK2.