title: Histologic and electrophysiological study of nerve regeneration using a polyglycolic acid-collagen nerve conduit filled with collagen sponge in canine model.
abstract: OBJECTIVE
  To determine the rate of achieving electrophysiologically proved functional recovery by autonomic nerve regeneration, with the aid of an artificial nerve conduit.
  
  
  METHODS
  A polyglycolic acid (PGA) collagen nerve conduit filled with collagen sponge was interposed in a 10-mm-long gap of the right hypogastric nerve (HGN) in 16 dogs. Histologic evaluation of nerve regeneration and electrophysiological analysis at 2 weeks and 2, 3, 4, 5, 6, 7, and 8 months (n = 2, each) after surgery was performed, measuring the responses for the spermatic ducts (SD), bladder neck (BN), and prostate contraction, by stimulating the right lumbar splanchnic nerves (LSNs) from L2 to L4, after transection of the left HGN to eliminate substitutive pathways.
  
  
  RESULTS
  Two months after implantation, the regenerated neurofilaments were successfully extended through the graft from the proximal-to-distal direction. In 2 control dogs, electrostimulation of the right LSNs induced elevation of the intraluminal pressure of the SD, elevation of the BN pressure, and prostate contraction. No responses were observed in all dogs up to 6 months of follow-up after implantation. In 1 dog with a 7-month follow-up, electrostimulation elicited elevation of BN pressure alone. In both dogs with an 8-month follow-up, electrostimulation induced similar responses to control in all SD, BN, and prostate; however, after excision of the area of the interposed right HGN, no response was observed.
  
  
  CONCLUSIONS
  These results proved that regeneration of a 10-mm gap of the HGN, using a novel PGA-collagen nerve conduit could be achieved within 8 months.
authors.affiliation: Department of Urology, Kyoto Prefectural University of Medicine, 11-1-603 shinmeimiyahigashi, Uji, Kyoto, Japan. mischievous@kve.biglobe.ne.jp
authors.forename: Kei
authors.initials: K
authors.lastname: Suzuki
authors.forename: Akihiro
authors.initials: A
authors.lastname: Kawauchi
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Nakamura
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Itoi
authors.forename: Tadao
authors.initials: T
authors.lastname: Ito
authors.forename: Jintetu
authors.initials: J
authors.lastname: So
authors.forename: Osamu
authors.initials: O
authors.lastname: Ukimura
authors.forename: Akeo
authors.initials: A
authors.lastname: Hagiwara
authors.forename: Hisakazu
authors.initials: H
authors.lastname: Yamagishi
authors.forename: Tsuneharu
authors.initials: T
authors.lastname: Miki
mesh_terms: D000818:Animals; D003094:Collagen; D004285:Dogs; D055724:Electrophysiological Phenomena; D008297:Male; D009416:Nerve Regeneration / Q000502:physiology*; D011100:Polyglycolic Acid
chemical_list: D011100:Polyglycolic Acid; D003094:Collagen