Early effects of sodium iodate on the directly recorded standing potential of the eye and on the c-wave of the DC registered electroretinogram in albino rabbits.

Abstract

The early effects of intravenously administered sodium iodate (NaIO3) on the directly recorded standing potential (SP) of the eye and on the c- and b-waves of the DC registered ERG were studied in 8 anaesthetized albino rabbits. In 5 of 6 animals obtaining 40 mg NaIO3/kg bwt. the SP decreased immediately following the injection, and had attained a level 3.5 - 4 mV below the original one after 1 h. The c-wave declined rapidly and 6 min after the injection it was replaced by a large cornea-negative potential. The b-wave was relatively unchanged except in one animal. In 2 rabbits treated with 30 mg NaIO3/kg btw. and in the 6th animal obtaining 40 mg NaIO3/kg bwt. an SP increase instead of a decrease was seen, and the c-wave was more slowly (about 22 min after the injection) replaced by the cornea-negative potential. The b-wave was somewhat increases. These results demonstrate the dose-related and inter-individual variability in the SP reaction to NaIO3 and are in good agreement with the well-known ultrastructural pigment epithelial injury and c-wave changes produced by this substance.