(R)-4-(1-Aminoethyl)-N-1H-pyrrolo[2,3-b]pyridin-4-ylbenzamide

Y-33075 (Y-39983) is a potent ROCK inhibitor, with an IC ₅₀ of 3.6 nM. It also inhibits PKC and CaMKII more potently than Y-27632, and the IC ₅₀ s of Y-27632 and Y-33075 for PKC are 9.0 μM and 0.42 μM, respectively, whereas the IC ₅₀ s of Y-27632 and Y- 33075 for CaMKII are 26 μM and 0.81 μM, respectively. The IC ₅₀ s of Y-27632 and Y-33075 for PKC are 82 and 117 times those for ROCK, respectively, whereas the IC ₅₀ s of Y-27632 and Y-33075 for CaMKII is 236 and 225 times those for ROCK, respectively. Y-33075 (Y-39983, 10 μM) extends neurites in the retinal ganglion cells (RGCs) compared with those in RGCs treated without Y-39983. It (Y-39983, 1 μM) inhibits the contraction of rabbit ciliary artery segments evoked by histamine in Ca ²⁺ -free solutions. Y-33075 ( 10 μM) shows no effect on the [Ca ²⁺ ]i increase with the high-potassium (high-K) solution.