title: The Effect of Sildenafil on Recuperation from Sciatic Nerve Injury in Rats.
abstract: BACKGROUND
  Severe functional and anatomical defects can be detected after the peripheral nerve injury. Pharmacological approaches are preferred rather than surgical treatment in the treatment of nerve injuries.
  
  
  OBJECTIVE
  The aim of this study is to perform histopathological, functional and bone densitometry examinations of the effects of sildenafil on nerve regeneration in a rat model of peripheral nerve crush injury.
  
  
  METHODS
  Animal experiment.
  
  
  METHODS
  The study included a total of thirty adult Sprague-Dawley rats that were divided into three groups of ten rats each. In all rats, a crush injury was created by clamping the right sciatic nerve for one minute. One day before the procedure, rats in group 1 were started on a 28-day treatment consisting of a daily dose of 20 mg/kg body weight sildenafil citrate given orally via a nasogastric tube, while the rats in group 2 were started on an every-other-day dose of 10 mg/kg body weight sildenafil citrate. Rats from group 3 were not administered any drugs. Forty-two days after the nerve damage was created, functional and histopathological examination of both sciatic nerves and bone densitometric evaluation of the extremities were conducted.
  
  
  RESULTS
  During the rotarod test, rats from group 3 spent the least amount of time on the rod compared to the drug treatment groups at speeds of 20 rpm, 30 rpm and 40 rpm. In addition, the duration for which each animal could stay on the rod throughout the accelerod test significantly reduced in rats from group 3 compared to rats from groups 1 and 2 in the 4-min test. For the hot-plate latency time, there were no differences among the groups in either the basal level or after sciatic nerve injury. Moreover, there was no significant difference between the groups in terms of the static sciatic index (SSI) on the 42(nd) day (p=0.147). The amplitude was better evaluated in group 1 compared to the other two groups (p<0.05). Under microscopic evaluation, we observed the greatest amount of nerve regeneration in group 1 and the lowest in group 3. However, this difference was not statistically significant. Moreover, there was no significant difference in the bone mineral density (BMD) levels among the groups.
  
  
  CONCLUSIONS
  We believe that a daily single dose of sildenafil plays an important role in the treatment of sciatic nerve damage and bone healing and thus can be used as supportive clinical treatment.
authors.affiliation: Department of Orthopaedics and Traumatology, İnönü University School of Medicine, Malatya, Turkey.
authors.forename: Mehmet Fatih
authors.initials: MF
authors.lastname: Korkmaz
authors.affiliation: Department of Pharmacology, İnönü University School of Medicine, Malatya, Turkey.
authors.forename: Hakan
authors.initials: H
authors.lastname: Parlakpınar
authors.affiliation: Department of Orthopaedics and Traumatology, İnönü University School of Medicine, Malatya, Turkey.
authors.forename: Mehmet Fethi
authors.initials: MF
authors.lastname: Ceylan
authors.affiliation: Department of Physical Therapy and Rehabilitation, Van Yüzüncü Yıl University School of Medicine, Van, Turkey.
authors.forename: Levent
authors.initials: L
authors.lastname: Ediz
authors.affiliation: Department of Pathology, İnönü University School of Medicine, Malatya, Turkey.
authors.forename: Emine
authors.initials: E
authors.lastname: Şamdancı
authors.affiliation: Department of Nuclear Medicine, İnönü University School of Medicine, Malatya, Turkey.
authors.forename: Ersoy
authors.initials: E
authors.lastname: Kekilli
authors.affiliation: Department of Pharmacology, İnönü University School of Medicine, Malatya, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Sağır
keywords: Bone density; peripheral nerve injuries; rotarod test; sciatic nerve; sildenafil