Hydroxyl Fasudil, an Inhibitor of Rho Signaling, Improves Erectile Function in Diabetic Rats: A Role for Neuronal ROCK

The pathogenesis of diabetic erectile dysfunction (ED) includes neuropathy, but the molecular basis for neurogenic ED is incompletely understood. The RhoA/ROCK pathway has been implicated in diabetic neuropathy and in ED, but its role in diabetic neurogenic ED is not known. The aim of this study was to determine whether hydroxyl fasudil, a ROCK inhibitor, affects diabetic neuropathy‐related ED. Type 1 diabetes mellitus was induced in male rats by streptozotocin (75 mg/kg, intraperitoneally). After 8 weeks, diabetic rats were administered hydroxyl fasudil, a selective ROCK inhibitor (10 mg/kg/day, intraperitoneally) or vehicle, for 4 weeks. Age‐matched control, nondiabetic, rats were treated intraperitoneally for 4 weeks with saline. At week 12, after a 2 day washout, neuro‐stimulated erectile function was evaluated. Major pelvic ganglia (MPG) were collected for Western blot analysis of RhoA, ROCK‐1, ROCK‐2, phospho (P)‐AKT (Ser473), and P‐phosphatase and tensin homolog (P‐PTEN) (Ser380/Thr382/383). Effect of ROCK inhibitor hydroxyl fasudil on erectile function and ROCK/P‐AKT/P‐PTEN pathway in the MPG of diabetic rats. Erectile response was significantly (P