The electroretinogram of the living extracorporeal bovine eye. The influence of anoxia and hypothermia.

A technique is presented for recording the bovine ERG (electroretinogram) from an isolated perfused preparation, the living extracorporeal bovine eye. By using this method, properties of the bovine ERG response were investigated under anoxic and hypothermic conditions. Retinal anoxia resulted in reduction of ERG waves in the following order: b-wave, slow positive component, and a-wave. The b-wave was most sensitive to the anoxia and diminished at 37° C. in 5 minutes while the a-wave showed only 60 per cent decrease during 6 minutes of anoxia. In recovery phase from the anoxia, ERG waves showed enhancement in the following order: a-wave, slow positive component, and b-wave. With anoxia of 60 minutes, complete recovery of the ERG never occurred upon reperfusion. When temperature was reduced to 30° C. a remarkable decline of oscillatory potential was observed. Slight decreases of amplitude and prolongation of peaking times of aand b-waves were also observed. The ERG responses were moderately well preserved at 30° C. for a period of hours, while lower temperature resulted in a deterioration increasing with time.