Vacuum erecti on device(VED),used to treat radical prostatectomy(RP)-associated erectile dysfunction,has attracted con siderable attention.However,the optimal negative pressure remains to be determined.This investigation explored the optimal pressure for VED therapy in penile rehabilitation.Thirty-six 9-week-old male rats were randomly divided into six groups:control groups(sham group,bilateral cavernous nerve crush[BCNC]group)and VED therapy groups(-200 mmHg group,-300 mmHg group,-400 mmHg group,-500 mmHg group).BCNC group and VED therapy groups underwent BCNC surgery.Intracavernosal pressure(ICP)/mean arterial pressure(MAP)ratio was calculated to assess erectile function.Mass on's trichrome(MT)staining,terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)assay,immunohistochemistry,and real-time polymerase chain reaction(RT-PCR)were performed to explore cellular and molecular changes of the penis.Compared to the BCNC group,ICP/MAP ratios in all VED treatment groups were improved significantly(all P<0.05),but there were no statistically significant differences among VED therapy groups.With increased pressure,complications gradually emerged and increased in frequency.Expression of molecular indicators,such as endothelial nitric oxide synthase(eNOS)and alpha-smooth muscle actin(a?SMA),increased after VED therapy,and hypoxia-inducible factor la(HIF-la)and transforming growth factor beta(TGF-p)decreased.In addition,VED therapy improved the outcomes of MT and TUNEL assay.This investigation demonstrated a pressure of-200 mmHg in a rat model is optimal for VED therapy for penile rehabilitation after RP.No further benefits were observed with increased pressure,despite an increase in complications.
