title: Effects of α-MSH on ischemia/reperfusion injury in the rat sciatic nerve.
abstract: BACKGROUND
  Ischemia/reperfusion (I/R) causes the production of toxic free radicals and leads to pathological changes in nerve tissue. We investigated the effect of alpha-melanocyte stimulating hormone (α-MSH) in a rat model for sciatic nerve I/R and discuss the possible cytoprotective and antioxidant mechanism of α-MSH against ischemic fiber degeneration.
  
  
  METHODS
  Experiments were performed using 42 adult male Wistar rats. Rats were divided into six experimental groups: control group, ischemia group, I/R groups, and α-MSH treated groups. Ischemia was produced by clamping of the femoral vessels. Immediately after ischemia that lasted 3 h, 75 μg/kg of α-MSH was administered subcutaneously before reperfusion and the tissue malondialdehyde (MDA) level was evaluated as an indicator of lipid peroxidation in groups with different reperfusion periods.
  
  
  RESULTS
  The reperfusion injury did not begin in the first hour of reperfusion after 3 h of ischemia, and MDA levels increased on the first day of reperfusion. During the first day, blood MDA levels were decreased in the α-MSH group compared to the control group. The tissue from animals pre-treated with α-MSH showed fewer morphological alterations. Myelin breakdown was significantly diminished after treatment with α-MSH, and the ultrastructural features of axons showed remarkable improvement. Two-way analysis of variance was used for comparing three or more groups. When a significant difference existed, the post-hoc multiple-comparison test was applied to demonstrate the differences.
  
  
  CONCLUSIONS
  The results confirm that pre-treatment with α-MSH after ischemia protected the peripheral nerves against I/R injury.
authors.affiliation: Ministry of Health Diskapi Yildirim Beyazit Research and Educational Hospital 1  Neurosurgery Clinic, 06610, Ankara, Turkey.
authors.forename: Erhan
authors.initials: E
authors.lastname: Turkoglu
authors.forename: Gökhan
authors.initials: G
authors.lastname: Serbes
authors.forename: Habibullah
authors.initials: H
authors.lastname: Dolgun
authors.forename: Sinem
authors.initials: S
authors.lastname: Oztuna
authors.forename: Ozlen T
authors.initials: OT
authors.lastname: Bagdatoglu
authors.forename: Necat
authors.initials: N
authors.lastname: Yilmaz
authors.forename: Celal
authors.initials: C
authors.lastname: Bagdatoglu
authors.forename: Zeki
authors.initials: Z
authors.lastname: Sekerci