Amniattalab A * [1] , Tamaddonfard E [2] , Cheraghian S [3]   Received: 1 Nov, 2009 Accepted: 27 Jan, 2010  Abstract  Background & Aims : Histidine is an essential amino acid. In this study, both histidine effect on nerve function index and histopathological changes in nerve regeneration process were evaluated in rats with crushed sciatic nerve.  Materials & Methods : 57 rats were used to evaluate the sciatic nerve function index and to study the histopathological sciatic nerve sections stained with three methods. Effective factors in nerve regeneration like number of Schwann cells nucleus and myelinated nerve fibers were studied.  Results: There was a significant reduce in sciatic function index (p<0.05) a significant reduce in the case groups and a significant increase in numbers of Schwann cells nucleus (p<0.05) in histidine 400mg/kg group compared with the control group(normal saline). In histidine 400mg/kg group, the numbers of myelinated nerve fibers on 42nd day increased significantly in comparision with days 14 and 28 (p<0.05).  Conclusion : It is revealed that in crush injuries, histidine in 400mg/kg dosage caused normal recurrence of sciatic nerve index. Recent researches have shown that during wallerian degeneration period the proliferation of Schwann cells is not necessary for regeneration and remyelination of peripheral nerves. But the increase of myelinated nerve fibers in histidine 400mg/kg group, on day 42 indicates the useful effect of histidine in peripheral nerve regeneration.  Keywords : Histidine, Experimental crush, Sciatic nerve, Behavioral study, Histopathology, Rat   Address : Department of Pathology, Faculty of Veterinary Medicine, Urmia Islamic Azad University, Urmia, Iran Tel: (+98) 9144414613   E-mail: a.amniattalab@iaurmia.ac.ir   Source: U rmia M ed J 2010: 21(2): 305 ISSN: 1027-3727
 [1] Assistant Professor of Pathology, Faculty of Veterinary Medicine, Urmia Islamic Azad University , Urmia, Iran (Corresponding Author)  [2] Associate Professor of Physiology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran  [3] B.Sc in Laboratory Sciences, Faculty of Veterinary Medicine, Urmia Islamic Azad University, Urmia, Iran | 
