The effect of cadmium on visual evoked potentials in alloxane-induced diabetic rats: relation to lipid peroxidation

Fifty-two healthy male Swiss albino rats, aged three months, were used in this study. They were divided into four groups: control (c), diabetic (D), cadmium (Cd), and diabetic + Cd (D+Cd). A diabetic condition was induced in D and D + Cd groups by administration of alloxane (5 mg/100 g). After this treatment, Cd and D + Cd groups were injected intraperitoneally with CdCl₂ (2 mg/kg week). At the end of the 2-month experimental period, flash visual evoked potentials (FVEPs) of the four groups were recorded with disk electrodes attached with electrode paste 0.5 cm in front of and behind the bregma. The mean latencies off the P₁, N₁, P₂, N₂ and P₃ components were significantly prolonged in the diabetic group compared with the control group. The mean latencies of P₃ in the D + Cd group and of P₁ and P₃ in the Cd group were longer than those of the control group. P₂N₂ amplitude of Cd and D + Cd groups were significantly increased compared with the control group. On the other hand, thiobarbituric acid-reactive substances (TBARS) were determined as an indicator of lipid peroxidation. Our data showed that Cd treatment and diabetic condition caused a significant increase of lipid peroxidation in kidney, brain, retina and lens. Received: 11 January 1999 / Accepted in revised form: 20 December 1999