title: Fibroblast growth factor-induced motor end plate regeneration in atrophic muscle.
abstract: OBJECTIVE
  To determine whether fibroblast growth factor 1 implanted with viable nerve into atrophic muscle will stimulate formation of functional, acetylcholine producing motor end plates.
  
  
  METHODS
  Twelve male Lewis rats underwent predenervation of the hamstring muscle 8 weeks before implantation of the nerve at a site distant from the original motor end plate. Six animals underwent implantation of the tagged nerve ending into atrophic muscle with 50 microgram of fibroblast growth factor 1 in a fibrin adhesive carrier (group 1). Three animals underwent implantation with nerve, fibrin adhesive, and no fibroblast growth factor 1 (group 2); and three animals underwent implantation with fibroblast growth factor 1 and fibrin adhesive with no nerve (group 3). Animals were killed 9 weeks after implantation and nerve and muscle specimens were harvested.
  
  
  METHODS
  Histoenzymologic methods for acetylcholinesterase and silver impregnation of nerve fibers were performed 9 weeks after fibroblast growth factor 1-fibrin adhesive implantation. Variables included the number of motor end plates per highpower field and motor end plate length.
  
  
  RESULTS
  Robust axonal sprouting and formation of multiple motor end plates were found arborized in serial fashion equidistant around the implanted nerve ending. Rare extrasynaptic staining occurred. End plate lengths were significantly shorter in the fibroblast growth factor 1-treated muscles (group 1) than in the specimens without fibroblast growth factor 1 (group 2) (31.2 vs 58.5 micron; P>001, paired t test). The arborization of motor end plates, rare extrasynaptic staining, and shorter end plate lengths seen in group 1 were all consistent with mature motor end plates. Controls (group 3) displayed limited motor end plate formation and extensive extrasynaptic staining typical of denervation.
  
  
  CONCLUSIONS
  This study presents encouraging evidence that fibroblast growth factor 1 with fibrin adhesive carrier can facilitate the reinnervation of atrophied muscle by enhancing the formation or revitalization of motor end plates. Future studies will address muscle function and use of different carrier materials.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Illinois Hospital, Chicago, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Walter
authors.forename: D M
authors.initials: DM
authors.lastname: Toriumi
authors.forename: B S
authors.initials: BS
authors.lastname: Patt
authors.forename: T K
authors.initials: TK
authors.lastname: Bhattacharyya
authors.forename: K
authors.initials: K
authors.lastname: O'Grady
authors.forename: J B
authors.initials: JB
authors.lastname: Caulfield
authors.forename: J A
authors.initials: JA
authors.lastname: Thompson
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004337:Drug Carriers; D004353:Drug Evaluation, Preclinical; D015718:Fibrin Tissue Adhesive / Q000494:pharmacology; D005346:Fibroblast Growth Factors / Q000494:pharmacology*; D008297:Male; D009045:Motor Endplate / Q000187:drug effects*; D009121:Muscle Denervation; D009133:Muscular Atrophy / Q000188:drug therapy* / Q000503:physiopathology; D009416:Nerve Regeneration / Q000187:drug effects*; D051381:Rats; D011917:Rats, Inbred Lew; D012092:Replantation; D012584:Sciatic Nerve / Q000601:surgery*
chemical_list: D004337:Drug Carriers; D015718:Fibrin Tissue Adhesive; D005346:Fibroblast Growth Factors