Hannan et al. used a nonselective ROCK-1 inhibitor (Y-27632) for intracavernosal injection in a rat model of CN injury, and two weeks later, the rats recovered erectile function, significantly upregulated both nNOS and eNOS expression, and effectively inhibited apoptosis of nNOS-positive axons [36]. Here, NOS1 is linked to cyclic hematopoiesis.