Effect of prior oxygen exposure on the electroretinographic responses of infant rats.
OBJECTIVE
To study electroretinographic responses of infant rats with a history of exposure to high-ambient oxygen.


METHODS
Electroretinographic responses to a range of full-field stimuli were recorded from 13-day-old (n = 8) and 18-day-old (n = 10) rats with a history of intermittent exposure to 80% oxygen and age-matched controls. The a-waves were fitted with a model of rod cell sensitivity and saturated response amplitude. The amplitudes and implicit times of the b-wave and oscillatory wavelets were examined as a function of stimulus energy. Response parameters in oxygen-exposed rats were compared to those in controls.


RESULTS
The amplitude of the saturated rod response was reduced in oxygen-exposed 13-day-old but not 18-day-old rats. The sensitivity of the rod response was reduced in both 13- and 18-day-old oxygen-exposed rats. The saturated amplitude and sensitivity of the b-wave did not differ significantly between oxygen-exposed and control rats age 13 days, but both amplitude and sensitivity were significantly decreased in 18-day-old oxygen-exposed rats. Oscillatory potentials, which could be investigated only in 18-day-old rats, showed significant attenuation of OP3 but not OP4 amplitudes in the oxygen-exposed rats. The sensitivity of OP2 did not differ significantly between oxygen-exposed and control rats. The avascular area in the oxygen-exposed rats was not correlated with any of the rod cell, b-wave, or oscillatory potential response parameters.


CONCLUSIONS
The function of the rod photoreceptors, as well as the inner retina, is altered in infant rats with a history of oxygen exposure.
Reynaud
X
X
Department of Ophthalmology, Childen's Hospitalk, Boston, MA 02115, USA.
Hansen
R M
RM
Fulton
A B
AB
D000332:Aerobiosis; D000818:Animals; D000831:Animals, Newborn; D004596:Electroretinography / Q000187:drug effects; D006801:Humans; D007231:Infant, Newborn; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D010100:Oxygen / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000187:drug effects / Q000502:physiology*; D017948:Retinal Rod Photoreceptor Cells / Q000187:drug effects / Q000502:physiology; D012178:Retinopathy of Prematurity / Q000209:etiology / Q000503:physiopathology*
D010100:Oxygen