title: Brain-derived neurotrophic factor and collagen tubulization enhance functional recovery after peripheral nerve transection and repair.
abstract: OBJECTIVE
  To investigate the effect of brain-derived neurotrophic factor (BDNF) and collagen tubulization (CT) on the regeneration of transected peripheral nerves. METHODS AND DESIGNS: The left sciatic nerve of 40 Sprague-Dawley rats was transected then repaired using one of four techniques; epineurial coaptation, CT, CT with BDNF delivered by an osmotic pump to the repair site, or CT with BDNF covalently cross-linked to the collagen matrix (CT/linked-BDNF). Sciatic functional indices were measured preoperatively at 10-day intervals for 90 days. Segments of the sciatic nerves proximal and distal to the repair site were harvested at 90 days for histologic and morphometric evaluation.
  
  
  RESULTS
  Animals repaired by CT/linked-BDNF (n=10) demonstrated the most favorable functional recovery of all groups, with statistically significant differences seen compared with animals repaired by CT (n=10, P=.05) and epineural coaptation (n=9, P<.001). Animals repaired by CT with BDNF delivered by an osmotic pump (n=8) and CT also showed statistically superior functional recovery compared with those repaired by epineurial coaptation (P=.005 and P=.02, respectively). Nerves repaired by CT/linked-BDNF had the largest mean axon diameters proximal and distal to the repair site.
  
  
  CONCLUSIONS
  Brain-derived neurotrophic factor and CT improve the rate and the degree to which recovery of sciatic function occurs after nerve transection and repair. Animals repaired by CT/BDNF-linked demonstrated the most favorable functional recovery of all groups. Animals whose repair technique included BDNF had the largest mean axon diameters of all groups.
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, Stanford University Medical Center, Calif., USA.
authors.forename: D S
authors.initials: DS
authors.lastname: Utley
authors.forename: S L
authors.initials: SL
authors.lastname: Lewin
authors.forename: E T
authors.initials: ET
authors.lastname: Cheng
authors.forename: A N
authors.initials: AN
authors.lastname: Verity
authors.forename: D
authors.initials: D
authors.lastname: Sierra
authors.forename: D J
authors.initials: DJ
authors.lastname: Terris
mesh_terms: D000818:Animals; D019208:Brain-Derived Neurotrophic Factor; D003094:Collagen / Q000494:pharmacology*; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D015918:Infusion Pumps, Implantable; D008297:Male; D009416:Nerve Regeneration / Q000187:drug effects*; D009419:Nerve Tissue Proteins / Q000494:pharmacology*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000187:drug effects* / Q000293:injuries* / Q000473:pathology / Q000601:surgery; D016037:Single-Blind Method; D013536:Suture Techniques
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D009419:Nerve Tissue Proteins; D003094:Collagen