title: Calcitonin pump improves nerve regeneration after transection injury and repair.
abstract: BACKGROUND
  After nerve injury, excessive calcium impedes nerve regeneration. We previously showed that calcitonin improved nerve regeneration in crush injury. We aimed to validate the direct effect of calcitonin on transected and repaired nerve.
  
  
  METHODS
  Two rat groups (n = 8) underwent sciatic nerve transection followed by direct repair. In the calcitonin group, a calcitonin-filled mini-osmotic pump was implanted subcutaneously, with a catheter parallel to the repaired nerve. The control group underwent repair only, without a pump. Evaluation and comparison between the groups included: (1) compound muscle action potential recording of the extensor digitorum longus (EDL) muscle; (2) tetanic muscle force test of EDL; (3) nerve calcium concentration; and (4) nerve fiber count and calcified spot count.
  
  
  RESULTS
  The calcitonin pump group showed superior recovery.
  
  
  CONCLUSIONS
  Calcitonin affects injured and repaired peripheral nerve directly. The calcitonin-filled mini-osmotic pump improved nerve functional recovery by accelerating calcium absorption from the repaired nerve. This finding has potential clinical applications.
authors.affiliation: Department of Plastic Surgery, Medical College of Wisconsin, 8700 Watertown Plank Road, Milwaukee, Wisconsin, 53226, USA.
authors.forename: Ji-Geng
authors.initials: JG
authors.lastname: Yan
authors.forename: John
authors.initials: J
authors.lastname: Logiudice
authors.forename: John
authors.initials: J
authors.lastname: Davis
authors.forename: Lin-Ling
authors.initials: LL
authors.lastname: Zhang
authors.forename: Michael
authors.initials: M
authors.lastname: Agresti
authors.forename: James
authors.initials: J
authors.lastname: Sanger
authors.forename: Hani S
authors.initials: HS
authors.lastname: Matloub
authors.forename: Robert
authors.initials: R
authors.lastname: Havlik
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002116:Calcitonin / Q000008:administration & dosage*; D002118:Calcium / Q000378:metabolism; D004195:Disease Models, Animal; D004576:Electromyography; D005456:Fluorescent Dyes; D015918:Infusion Pumps, Implantable; D053580:Muscle Strength / Q000187:drug effects; D018482:Muscle, Skeletal / Q000503:physiopathology; D009412:Nerve Fibers / Q000473:pathology; D009416:Nerve Regeneration / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020426:Sciatic Neuropathy / Q000188:drug therapy* / Q000473:pathology; D013997:Time Factors; D014945:Wound Healing / Q000187:drug effects
chemical_list: D005456:Fluorescent Dyes; D002116:Calcitonin; D002118:Calcium
keywords: calcitonin; nerve regeneration; nerve repair; osmotic pump; peripheral nerve injury