Studies on developmental alterations in the electroretinogram in rats after post-natal exposure to lead.

The effects of post-natal exposure to lead on the development of the electroretinogram in rats were studied. Newborn rats were fed with lead acetate by gastric intubation and weight and age-matched control rats were given sodium acetate in a similar way. At 15 and 26 days of age the lead concentrations in blood were on average 298 micrograms/100 ml and 80 micrograms/100 ml, respectively. The brain concentrations of lead were on average 248 micrograms/100 mg in the 15-day-old lead-fed animals and 244 micrograms/100 mg in the 26-day-old ones. Lead produced a transient depression of the post-natal development of the electroretinogram. A decrease in the amplitudes of the a- and b-waves, as well as an increase in the peak times of these potentials were found in the 15-day-old animals. The ERGs of the 26-day-old animals did not differ from controls. There were no morphological changes of the retina.