Reduction in Peyronie's‐like plaque size using a vacuum erection device in a rat model of Peyronie's disease via the TGF‐β/SMAD signalling pathway

Peyronie's disease (PD) is a fibrotic disorder of the tunica albuginea (TA). This study aimed to determine the therapeutic effects of a vacuum erection device (VED) in an animal model of PD and explore the possible mechanisms. Twenty‐seven male Sprague‐Dawley rats were used. The sham group (group A) (N = 9) received a 50‐μl‐saline vehicle injection into the TA, while the remaining 18 rats (groups B and C) received a TGF‐β1 injection into the TA. The treatment group (group C) underwent VED therapy for 10 days after the TGF‐β1 injection. Erectile function was then assessed at day 42. Rats injected with TGF‐β1 showed significantly lower intracavernous pressures than those in the sham group (p < 0.0001). After VED therapy, erectile function was significantly better in the treatment group than in the PD group (group B) (p < 0.0147). Masson's trichrome staining confirmed Peyronie's‐like plaques at the TGF‐β1 injection site in the PD group. Furthermore, the treatment group showed markedly smaller fibrotic plaque sizes than the PD group. A significant increase in TGF‐β1, SMAD2, SMAD3 and p‐SMAD2/3 protein expression was observed 6 weeks after the TGF‐β1 injection. However, the expression of the same proteins decreased after VED therapy. Protein expression trends were confirmed using immunohistochemistry analysis. The findings of this study demonstrate that VED therapy can reduce Peyronie's‐like plaque size in a rat model of PD while simultaneously improving erectile function.