An ATP-competitive inhibitor of ROCK-I and ROCK-II (IC50s = 102 and 276 nM, respectively at a concentration of 40 μM ATP); selective for ROCK over 79 other kinases at IC50 values up to 10 μM but had IC50 values ranging from 1 to 10 μM for RSK, PKB, PKCδ, and MSK-1; selective for ROCK over 115 receptor and enzyme targets at IC50 values up to 10 μM, but it does inhibit the serotonin transporter and μ-opioid receptors with IC50s values of 1.1 and 8.9 μM, respectively; inhibits ROCK-mediated phosphorylation of MYPT, thrombin-induced stress fiber formation, PDGF-induced proliferation, and MCP-1-stimulated chemotaxis; relaxes precontracted isolated arteries from various species (IC50s = 122-280 nM) and precontracted corpora cavernosa in both healthy and diabetic animals (IC50s = 0.05-0.42 μM); inhibits ET-1-induced constriction of rat and human arteries (Emaxs = 24-83% of control)