Electrophysiologic evaluation of retinal pigment epithelial damage induced by photic exposure.
OBJECTIVE
To evaluate the retinal pigment epithelial damage induced by light exposure.


METHODS
One eye of 20 rabbits was exposed to xenon light for 2 hours at an irradiance of 140 mW/cm2 at the surface of the cornea. The contralateral eye served as a control. Forty-eight hours after the light exposure, corneal direct-coupled electroretinograms and the 7% NaHCO3 (bicarbonate) responses of the standing potential were recorded.


RESULTS
The amplitudes of the a-, b-, and c-waves of the electroretinograms were significantly reduced in the light-exposed eyes, with the c-waves more reduced than the a- and b-waves. The bicarbonate response was also significantly reduced in the irradiated eyes.


CONCLUSIONS
The decrease of the bicarbonate response of the standing potential indicated that significant functional damage of the retinal pigment epithelium was induced by the light exposure.
Kawano
Toshio
T
Department of Ophthalmology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu 431-3192, Japan. tk4649@pj8.so-net.ne.jp
Kato
Masaru
M
D000818:Animals; D004596:Electroretinography; D007275:Injections, Intravenous; D008027:Light; D008564:Membrane Potentials; D010857:Pigment Epithelium of Eye / Q000502:physiology / Q000528:radiation effects*; D011817:Rabbits; D011833:Radiation Injuries, Experimental / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D012164:Retinal Diseases / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D017693:Sodium Bicarbonate / Q000008:administration & dosage; D014978:Xenon
D014978:Xenon; D017693:Sodium Bicarbonate