title: A Time Course Study of Different Methods of Extraneural Scar Induction in a Rat Model.
abstract: Background Extraneural scar formation is a challenging problem in nerve repair. Rodent models of scar induction, with their high regenerative capacity, suffer from lack of comparable similarities with human cases. In this study, we attempted to find a reliable and reproducible method of extraneural scarring with a significant impact on the peripheral nerve function. Methods A total of 60 rats were divided into three scar induction groups: abrasion (with a small piece of compressed steel wool), mincing (with extracorporeal mincing of adductor muscle and a 5-mm wide strip of the anterior border of the biceps femoris), and electrocoagulation (with a bipolar coagulator). Extraneural scarring was evaluated macroscopically and histologically during 8 weeks. The tibial functional index was used for behavioral analysis. Results Among three different physical methods of scar induction that were applied, electrocoagulation had the most functional impairment (p < 0.001, two-way analysis of variance); whereas mincing produced the most adhesive and intensive scar, morphologically (p < 0.001). Conclusion We conclude that: (1) the impact of the extraneural scar on the nerve is morphologically and functionally different, based on the method of scarring; (2) to achieve a scar model comparable to the human situation, a method in which the involved nerve is functionally impaired, is preferred over the ones that merely produce a bulky scar.
authors: Research Center for Neural Repair (RCNR), University of Tehran, Tehran, Iran.
authors: Leila Oriady
authors: LO
authors: Zanjani
authors: Research Center for Neural Repair (RCNR), University of Tehran, Tehran, Iran.
authors: Masoumeh
authors: M
authors: Firouzi
authors: Research Center for Neural Repair (RCNR), University of Tehran, Tehran, Iran.
authors: Mohammad Hossein
authors: MH
authors: Nabian
authors: Research Center for Neural Repair (RCNR), University of Tehran, Tehran, Iran.
authors: Shayan Abdollah
authors: SA
authors: Zadegan
authors: Research Center for Neural Repair (RCNR), University of Tehran, Tehran, Iran.
authors: Mohsen
authors: M
authors: Nategh
authors: Research Center for Neural Repair (RCNR), University of Tehran, Tehran, Iran.
authors: Reza
authors: R
authors: Erfanian
authors: Research Center for Neural Repair (RCNR), University of Tehran, Tehran, Iran.
authors: Ahmad Mohebbi
authors: AM
authors: Ashtiani
authors: Department of Orthopedic and Trauma Surgery, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors: Reza Shahryar
authors: RS
authors: Kamrani
mesh_terms: D000818:Animals; D002921:Cicatrix / Q000473:pathology*; D004195:Disease Models, Animal; D005260:Female; D006614:Hindlimb / Q000098:blood supply / Q000473:pathology*; D018919:Neovascularization, Physiologic; D059348:Peripheral Nerve Injuries / Q000473:pathology*; D010525:Peripheral Nerves / Q000473:pathology*; D011183:Postoperative Complications; D051381:Rats; D014945:Wound Healing