title: Local and systemic effects of low-dose transtympanic methotrexate: in vivo animal study.
abstract: OBJECTIVE
  To evaluate the safety of low-dose transtympanic methotrexate in a rat model.
  
  
  METHODS
  Experimental animal study.
  
  
  METHODS
  Tertiary training and research hospital.
  
  
  METHODS
  Twenty-four rats were randomly divided into three study groups. Diluted methotrexate solution was administered transtympanically to fill the middle-ear cavity, twice a week in group one and three times a week in group two. Ringer lactate solution was administered transtympanically three times a week in the control group.
  
  
  METHODS
  Local and systemic effects of low-dose transtympanic methotrexate.
  
  
  RESULTS
  In the methotrexate groups, middle-ear mucosal oedema was present in all animals. Auditory brainstem response thresholds indicated no inner-ear dysfunction in any group. Liver function and serum haemoglobin levels showed no statistically significant difference in any group. However, liver biopsies from groups one and two showed mild portal hyperaemia.
  
  
  CONCLUSIONS
  These findings are encouraging, and support further investigation of the topical application of methotrexate in autoimmune hearing diseases, as an alternative or adjunct to transtympanic steroids.
authors.affiliation: Department of Otorhinolaryngology (Clinic II), Sisli Etfal Training and Research Hospital, Istanbul, Turkey.
authors.forename: E
authors.initials: E
authors.lastname: Sozen
authors.affiliation: Department of Otorhinolaryngology (Clinic II), Sisli Etfal Training and Research Hospital, Istanbul, Turkey.
authors.forename: S B
authors.initials: SB
authors.lastname: Erol
authors.affiliation: Department of Otorhinolaryngology (Clinic II), Sisli Etfal Training and Research Hospital, Istanbul, Turkey.
authors.forename: O
authors.initials: O
authors.lastname: Yildirim
authors.affiliation: Department of Otorhinolaryngology (Clinic II), Sisli Etfal Training and Research Hospital, Istanbul, Turkey.
authors.forename: B U
authors.initials: BU
authors.lastname: Coskun
authors.affiliation: Department of Pathology, Sisli Etfal Training and Research Hospital, Istanbul, Turkey.
authors.forename: T
authors.initials: T
authors.lastname: Basak
authors.affiliation: Department of Otorhinolaryngology, Bakırkoy Dr Sadi Konuk Training and Research Hospital, Istanbul, Turkey.
authors.forename: F T
authors.initials: FT
authors.lastname: Kayhan
authors.affiliation: Department of Otorhinolaryngology (Clinic II), Sisli Etfal Training and Research Hospital, Istanbul, Turkey.
authors.forename: B
authors.initials: B
authors.lastname: Dadas
mesh_terms: D000818:Animals; D004432:Ear, Middle / Q000187:drug effects*; D016057:Evoked Potentials, Auditory, Brain Stem; D006309:Hearing; D007166:Immunosuppressive Agents / Q000008:administration & dosage*; D007552:Isotonic Solutions / Q000008:administration & dosage; D008297:Male; D008727:Methotrexate / Q000008:administration & dosage*; D051381:Rats; D017208:Rats, Wistar; D000077325:Ringer's Lactate; D014432:Tympanic Membrane / Q000187:drug effects*
chemical_list: D007166:Immunosuppressive Agents; D007552:Isotonic Solutions; D000077325:Ringer's Lactate; D008727:Methotrexate