title: Effects of chronic vardenafil treatment persist after end of treatment in rats with acute arteriogenic erectile dysfunction.
abstract: BACKGROUND
  In our previous study, chronic vardenafil treatment improved erectile function soon after the end of the treatment in rats with acute arteriogenic erectile dysfunction (ED).
  
  
  OBJECTIVE
  The aim of this study is to evaluate whether the effects of chronic vardenafil treatment persist after the end of treatment using rats with acute arteriogenic ED.
  
  
  METHODS
  Rats were randomly divided into three groups: (i) control; (ii) ligation; and (iii) vardenafil + no treatment. Rats in the ligation and vardenafil + no treatment groups underwent ligature of the bilateral internal iliac arteries to induce acute arteriogenic ED and were subsequently treated with vehicle or vardenafil (4.0 mg/kg/day), respectively, for 3 weeks. Subsequently, all rats were kept for a further 2 weeks with no treatment. Rats in the control group underwent sham surgery.
  
  
  METHODS
  Erectile function was assessed by changes in intracavernous pressure (ICP). Smooth muscle (SM)/collagen ratios in corpus cavernosum were analyzed by Masson trichrome staining. Transforming growth factor-β1 (TGF-β1 ) mRNA and protein levels in corpus cavernosum (CC) were, respectively, evaluated by real-time polymerase chain reaction (PCR) analysis and Western blotting analysis.
  
  
  RESULTS
  ICP/mean arterial pressure (MAP) in the ligation group remained significantly lower than that in control group (P < 0.01). Despite no treatment for 2 weeks, ICP/MAP in the var + no treatment group remained significantly higher than that in ligation group (P < 0.05). SM/collagen ratio in the ligation group remained significantly lower when compared with the control group (P < 0.01). The ratio in the var + no treatment group remained significantly higher when compared with the ligation group at 2 weeks after the end of treatment (P < 0.05). TGF-β(1) mRNA and protein levels did not differ among the groups.
  
  
  CONCLUSIONS
  The effects of chronic vardenafil treatment on erectile function and penile structure persist, even after the end of treatment, in acute arteriogenic ED rats.
authors.affiliation: Department of Hospital Pharmacy, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Hotta
authors.forename: Risa
authors.initials: R
authors.lastname: Ohno
authors.forename: Tomoya
authors.initials: T
authors.lastname: Kataoka
authors.forename: Mayumi
authors.initials: M
authors.lastname: Mikumo
authors.forename: Yu
authors.initials: Y
authors.lastname: Takahata
authors.forename: Masae
authors.initials: M
authors.lastname: Ohno
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Maeda
authors.forename: Kazunori
authors.initials: K
authors.lastname: Kimura
mesh_terms: D000818:Animals; D015153:Blotting, Western; D007093:Imidazoles / Q000627:therapeutic use*; D018783:Impotence, Vasculogenic / Q000188:drug therapy*; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D010410:Penile Erection / Q000187:drug effects; D010413:Penis / Q000737:chemistry / Q000187:drug effects; D058986:Phosphodiesterase 5 Inhibitors / Q000627:therapeutic use*; D010879:Piperazines / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D060888:Real-Time Polymerase Chain Reaction; D013450:Sulfones / Q000627:therapeutic use; D053773:Transforming Growth Factor beta1 / Q000032:analysis; D014227:Triazines / Q000627:therapeutic use; D000069058:Vardenafil Dihydrochloride
chemical_list: D007093:Imidazoles; D058986:Phosphodiesterase 5 Inhibitors; D010879:Piperazines; D013450:Sulfones; D053773:Transforming Growth Factor beta1; D014227:Triazines; D000069058:Vardenafil Dihydrochloride