EFFECT OF DIETARY SELENIUM, ZINC AND ALLOPURINOL SUPPLEMENTS ON PLASMA AND TISSUE MANGANESE LEVELS IN RATS WITH THIOCETAMIDE-INDUCED LIVER-CIRRHOSIS

The effect of thiocetamide-induced liver cirrhosis on plasma and tissu e manganese levels and the protective role of selenium, zinc and allop urinol supplements was investigated in rats. Control plasma and liver manganese (Mn) levels were found to be (mean +/- SD): 8.4 +/- 2.4 mg/L and 5.7 +/- 1.5 mg/g wet weight respectively. Plasma manganese levels were significantly increased (p < 0.001) whereas liver manganese leve ls were significantly reduced (p < 0.05) in the cirrhotic rats. Treatm ent with selenium, zinc and allopurinol reversed this trend and restor ed the manganese levels close to the normal values. Lung, spleen, and kidney manganese levels under control conditions were considerably low er than that of the liver tissue. However, these levels registered a s ignificant increase (p < 0.05) in cirrhotic rats and this change was n ormalized after selenium, zinc and allopurinol treatment. There were n o significant differences in the comparative efficacy of each of these protective agents. Zinc supplement considerably increased the plasma zinc levels and plasma Zn/Mn ratio had a good correlation with plasma zinc concentration. This ratio was significantly reduced in cirrhotic rats, but returned to the control level after zinc, selenium and allop urinol treatment. The results of this study indicate that the trace el ement, manganese, plays an important role in stabilizing cell structur e and that this effect is mediated possibly by preserving the antioxid ant activity of the tissues.