Affiliations: Division of Plastic and Reconstructive Surgery,
Washington University School of Medicine
Note: [] Correspondence to: Susan E. Mackinnon, M.D., Suite 17424, East
Pavilion, One Barnes Hospital Plaza, St. Louis, MO 63 1 10. Tel.: +314 362
4586; Fax: +314 367 0225.
Abstract: Purpose: The severe functional and sensory deficits seen following
injury to peripheral nerves makes facilitation of nerve regeneration a primary
goal of the reconstructive surgeon. This study examines whether daily
administration of FK506 or Cyclosporin A expedites peripheral nerve
regeneration following neurotmetic injury in a rat model Methods: Inbred
Buffalo rats were randomized to three experimental groups. Group I rats served
as untreated controls. Rats in groups II and III received daily subcutaneous
CsA (5 mg/kg), and FK506 (1 mg/kg), respectively. Each animal underwent
unilateral posterior tibial nerve transection with immediate epineurial
reapproximation. Functional recovery of the injured limb was assessed by serial
walking track analysis. Nerve regeneration was assessed histomorphometrically
via light microscopy. Results: Return of hindlimb function in control animals
occurred at 32 days post injury. CsA and FK506-treated transection animals
recovered at 26 and 18 days post injury, respectively. Statistically
significant greater fiber density and percent neural tissue were seen in FK506-
treated animals compared to control animals four weeks post transection.
Conclusions: This data suggest that the daily systemic administration of both
CsA and FK506 accelerate the rate of functional regeneration, following
neurotmetic injuries in tbc rat model. FK506's effect on nerve growth is
significantly greater than that of CsA.
