[The effect of gamma-aminobutyric acid injected into lateral brain ventricle of rats after prenatal cadmium intoxication on flash visual evoked potentials (FVEP)].

Purpose: To find out any influence of gamma-aminobutyric acid (GABA) injected into lateral brain ventricle in newborn rats prenatally exposed to cadmium (Cd).

Method: 18 white, Wistar, offspring rats were divided into 3 groups, each consisting of 6 rats (control, 5 ppm and 50 ppm of Cd in drinking water). Newborns were examined when they were 3-6 months old. FVEP were recorded before and after GABA injections. Two doses of GABA were used, 10 and 100 nmols. The statistic analysis with the test of t-Student was performed to estimate the amplitudes and latencies of the negative wave N1 and the next positive one P2. p < 0.05 was used to indicate significant difference.

Results: No significant changes in the latencies of peak N1 and P2 in the control and Cd 5 ppm groups (101-103%) after 10 nmols GABA were observed. However, the shortened (91-97%) of them was observed after both doses of GABA in Cd 50 ppm group. The mean value of amplitude of N1 in control rats increased to 127% after 10 nmols GABA and 142% after 100 nmols GABA. Moreover, the mean amplitude of P2 in this group increased to 108% and 146%, respectively. The high significant increase of the amplitudes of N1 (181-280%) and P2 (160-177%) waves were received after both doses of GABA in Cd groups.

Conclusion: Cadmium increased the sensitivity of GABA-receptors in the OUN.