title: Transcorneal electrical stimulation promotes survival of photoreceptors and improves retinal function in rhodopsin P347L transgenic rabbits.
abstract: OBJECTIVE
  To determine whether transcorneal electrical stimulation (TES) has neuroprotective effects on the photoreceptors, and whether it slows the rate of decrease of the electroretinogram (ERG) in rhodopsin P347L transgenic (Tg) rabbits.
  
  
  METHODS
  Six-week-old Tg rabbits received TES through a contact lens electrode on the left eye weekly for 6 weeks. The right eyes received sham stimulation on the same days. Electroretinograms (ERGs) were recorded before and at 12 weeks after the TES. After the last ERG recordings, the animals were euthanized for morphologic analysis of the retinas. Immunohistochemical (IHC) analysis was performed to detect the immunostaining by peanut agglutinin (PNA) and rhodopsin antibodies in the retinas.
  
  
  RESULTS
  The a- and b-wave amplitudes of the photopic ERGs and the b-wave amplitudes of the scotopic ERGs at higher stimulus intensities were significantly larger in the TES eyes than in the sham stimulated eyes (P<0.05, respectively). Morphologic analyses showed that the mean thickness of the outer nuclear layer (ONL) in the visual streak at 12 weeks was significantly thicker in TES eyes than in sham-stimulated eyes (P<0.05). IHC showed that the immunostaining by PNA and rhodopsin antibody in the TES-treated retinas was stronger than that in the sham-stimulated retinas.
  
  
  CONCLUSIONS
  TES promotes the survival of photoreceptors and preserves the ERGs in Tg rabbits. Although further investigations are necessary before using TES on patients, these findings indicate that TES should be considered for therapeutic treatment for RP patients with a P347L mutation of rhodopsin.
authors.affiliation: Department of Applied Visual Science, Osaka University Graduate School of Medicine, Osaka, Japan. takeshi.morimoto@ophthal.med.osaka-u.ac.jp
authors.forename: Takeshi
authors.initials: T
authors.lastname: Morimoto
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kanda
authors.forename: Mineo
authors.initials: M
authors.lastname: Kondo
authors.forename: Hiroko
authors.initials: H
authors.lastname: Terasaki
authors.forename: Kohji
authors.initials: K
authors.lastname: Nishida
authors.forename: Takashi
authors.initials: T
authors.lastname: Fujikado
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D003315:Cornea; D004195:Disease Models, Animal; D004558:Electric Stimulation / Q000379:methods*; D004596:Electroretinography; D007150:Immunohistochemistry; D020419:Photoreceptor Cells, Vertebrate / Q000473:pathology*; D011817:Rabbits; D012164:Retinal Diseases / Q000378:metabolism / Q000503:physiopathology / Q000628:therapy*; D012243:Rhodopsin / Q000235:genetics* / Q000378:metabolism
chemical_list: D012243:Rhodopsin