Purchase this article with an account.
Omar Gonzalez Gonzalez, Federico Bech, Ignacio Alcalde, Almudena Íñigo-Portugués, Jesus Merayo-Lloves, Carlos Belmonte; Morphological and functional characteristics of regenerating corneal nerves in mice following photorefractive surgery. Invest. Ophthalmol. Vis. Sci. 2016;57(12):906.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To define the morphological and electrophysiological changes developed by corneal sensory nerves following laser-induced damage to the cornea.
A 2 mm diameter lesion destroying all subbasal nerves inside was produced in the right eye cornea of 3 to 6 months C57BL6/J mice, using an excimer laser (VisXStar2). Uninjured left eyes were used as control. Nerve regeneration was studied 0, 3, 7, 15, 30 and 90 days after the injury. For electrophysiological studies, mice were sacrificed and eyes were excised, placed in a recording chamber and superfused with physiological saline. Temperature was regulated with a home-made Peltier device. Extracellular electrical activity of single sensory nerve endings of the corneal surface was recorded with a micropipette (Brock et al. 2001). Nerve terminal impulses (NTI) were amplify . Data were filtered and analyzed using Spike 2 software. At the end of the experiments, corneas were fixed and studied with immunofluorescence techniques against Beta-Tubulin III (Covance, San Diego, CA). Number, length, branching pattern and origin of regenerated subbasal leashes were measured using a Leica DM6000 microscope (Leica Microsystems, Walldroff, Germany) and FIJI image analysis software.
No NTI activity was detected in the injured area until 7 days after injury, when occasional, aberrant NTIs were observed coincident with the morphological appearance of short regenerative nerve sprouts arising at new basal laminae perforations. After 15 days the percentage of successful attempts to find an active nerve terminal in injured and control eyes was similar (30% and 26.9% respectively). The functional characteristics of the active terminals in injured eyes were roughly similar to those of control eyes. At this stage, axons extending from existing subbasal leashes to the center of the cornea were clearly observed. 90 days after injury, nerve terminals of all operated eyes showed normal functional characteristics in parallel with a restored subbasal plexus appearance and recovered density of epithelial nerve axons and terminals.
Following a laser ablation of the corneal subbasal plexus, nerve terminals recover in 7 to 15 days most of their morphological and functional properties. At 90 days, corneal nerves of treated eyes exhibit a normal function and the same general morphological appearance than in contralateral, uninjured eyes
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.
This PDF is available to Subscribers Only