Effects of iodate on intraretinal b and c waves of the cat electroretinogram

In 12 cats, the intravenous and intravitreal administrations of sodium iodate (SI) were performed to examine the effects on b and c waves of electroretinogram in the dark-adapted retina. The intravitreal SI (0.5-3.5 mM) produced the complete suppression of intraretinal b waves without remarkable changes of slow PIII and light-evoked [K+]o decrease in the subretinal space. Intravenous SI (30 mg/kg) also showed the suppression of intraretinal b waves. SI not only acted as a poison to the retinal pigment epithelium but also might block the post-synaptic response.