title: Amitriptyline and phenytoin prevents memory deficit in sciatic nerve ligation model of neuropathic pain.
abstract: BACKGROUND
  Phenytoin and amitriptyline are often reported to attenuate pain in chronic conditions. Information on their ability to ameliorate cognitive impairment associated with neuropathic pain remains unclear due to mixed results from studies. This study investigated the effects of phenytoin and amitriptyline on memory deficit associated with neuropathic pain.
  
  
  METHODS
  Twenty-eight adult male Wistar rats were randomly divided into four groups: A, B, C, and D (n=7). Groups A, B, C, and D served as sham control, sciatic nerve ligated untreated, sciatic nerve ligated receiving amitriptyline (5 mg/kg), and sciatic nerve ligated receiving phenytoin (10 mg/kg) respectively. Treatments lasted for 14 days, after which both 'Y' maze and novel object recognition test (NOR) were performed. On the last day of treatment, the animals were anesthetized and their brain excised, and the prefrontal cortices and sciatic nerve were processed histologically using hematoxylin and eosin.
  
  
  RESULTS
  There was memory impairment in the sciatic nerve ligated untreated group which was statistically significant (p<0.05) when compared to the phenytoin-treated, amitriptyline-treated, and sham control groups using the 'Y' maze and NOR tests. Histological quantification showed that the prefrontal cortices of the ligated animals showed increased neural population in comparison to normal control. These increases were significantly marked in the untreated ligated group. Sciatic nerve of untreated ligated group showed high demyelination and axonal degeneration which was ameliorated in the treated animals.
  
  
  CONCLUSIONS
  The administration of amitriptyline and phenytoin can ameliorate neuronal injury, demyelination, and memory impairment associated with neuropathic pain in Wistar rats.
authors.forename: Wahab Imam
authors.initials: WI
authors.lastname: Abdulmajeed
authors.forename: Ridwan Babatunde
authors.initials: RB
authors.lastname: Ibrahim
authors.forename: Azeez Olakunle
authors.initials: AO
authors.lastname: Ishola
authors.forename: Wasiu Gbolahan
authors.initials: WG
authors.lastname: Balogun
authors.forename: Ansa Emmanuel
authors.initials: AE
authors.lastname: Cobham
authors.forename: Abdulbasit
authors.initials: A
authors.lastname: Amin
mesh_terms: D000639:Amitriptyline / Q000494:pharmacology*; D000818:Animals; D004195:Disease Models, Animal; D008026:Ligation / Q000379:methods; D008297:Male; D008569:Memory Disorders / Q000517:prevention & control*; D009437:Neuralgia / Q000188:drug therapy*; D010147:Pain Measurement / Q000379:methods; D017288:Pain Threshold / Q000187:drug effects; D010672:Phenytoin / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D021641:Recognition, Psychology / Q000187:drug effects; D012584:Sciatic Nerve / Q000000981:diagnostic imaging*
chemical_list: D000639:Amitriptyline; D010672:Phenytoin