title: Rifabutin accumulates in the lens and reduces retinal function in the rabbit eye.
abstract: OBJECTIVE
  To study the toxicology of rifabutin in the rabbit eye with emphasis on retinal function and histopathology.
  
  
  METHODS
  Seven rabbits received a daily dose of rifabutin during 15 months. Six rabbits receiving only the vehicle were used as controls. Repeated standardized full-field electroretinograms (ERG) were assessed. After discontinuing treatment, the rabbits were killed and the cornea, the lens, and the sectioned retina was studied. Immunhistochemistry directed against vimentin, glial fibrillaryacidic protein (GFAP), protein kinase C (PKC), and peanut agglutinin (PNA) was performed.
  
  
  RESULTS
  Rifabutin was detected in serum of the treated rabbits. During treatment, the full-field ERG demonstrated significantly reduced b-wave amplitudes in the total rod-cone response as well as in the isolated rod and cone response compared with the recordings before treatment. The control rabbits did not demonstrate a reduction of the ERG amplitudes. The treated rabbits developed a discoloration of the lens, not seen in the control group. No retinal pathology was demonstrated using immunohistochemical methods.
  
  
  CONCLUSIONS
  Rifabutin causes a discoloration of the lens and reduces both rod and cone function in rabbits, but does not alter retinal morphology. Previous reports on ocular side effects caused by rifabutin are supported by the results of this study.
authors.affiliation: Department of Ophthalmology, and daggerHospital Pharmacy, University of Lund, Lund, Sweden. anna.cardiakidis_myers@med.lu.se
authors.forename: Anna Cardiakidis
authors.initials: AC
authors.lastname: Myers
authors.forename: Sten
authors.initials: S
authors.lastname: Kjellström
authors.forename: Anitha
authors.initials: A
authors.lastname: Bruun
authors.forename: Björn
authors.initials: B
authors.lastname: Isaksson
authors.forename: Fredrik
authors.initials: F
authors.lastname: Ghosh
authors.forename: Sten
authors.initials: S
authors.lastname: Andréasson
authors.forename: Vesna
authors.initials: V
authors.lastname: Ponjavic
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics / Q000633:toxicity*; D004596:Electroretinography / Q000187:drug effects*; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D007908:Lens, Crystalline / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008297:Male; D011493:Protein Kinase C / Q000378:metabolism; D011817:Rabbits; D012160:Retina / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D012164:Retinal Diseases / Q000139:chemically induced* / Q000378:metabolism / Q000503:physiopathology; D017828:Rifabutin / Q000493:pharmacokinetics / Q000633:toxicity*; D014746:Vimentin / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D005904:Glial Fibrillary Acidic Protein; D014746:Vimentin; D017828:Rifabutin; D011493:Protein Kinase C