Abstract:

Objective        To study chromium induced hearing damages and protective effects of zinc and selenium on hearing in rats. Methods      Twenty male and twenty female Wistar rats were randomly and averagely divided into the control group(A), the chromium poisoning group(B), the zinc protective group(C), and the selenium protective group(D). After 30 days of oral administration of physiological saline, 4mg/kg potassium dichromate, 2mg/kg zinc sulfate, and 2mg/kg sodium selenite, their auditory brainstem response (ABR) was detected. Results      ABR figures of chromium poisoning groups were extremely flat and theⅠand Ⅱ latencies of ABR waves were much longer and their wave peaks were much lower than those of the control group. TheⅠand Ⅱ latencies of the two ABR waves in group C were a little shorter than those of group B, and the latencies of group D were much shorter than those of group B, but both of them were still longer than those of group A. The two wave peaks of group C and group D were higher than those of group B but lower than those of group A. Conclusions      Hearing functions of rats might be partly damaged by chromium and zinc or selenium shows some protective effects. The protection of selenium is stronger than that of zinc.

Key words: Chromium poisoning; Hearing damages; Zinc; Selenium; Antagonistic effect