식이 단백질과 Cysteine수준이 흰쥐의 Cadmium중독에 미치는 영향 = Effect of Dietary Protein and Cysteine Levels on Cadmium Toxicity in Rats

다국어 초록 (Multilingual Abstract)

This study was perfomed to investigate the effect of dietary protein and cystein levels on cadmium toxicity in rats. Seventy-two male rats of Sprague-Dawely strain weighing 171±3g were blocked into 12 groups according to body weight, and were raised for 30 days. Cadmium chloride was given at levels of 0 or 400ppm, protein at levels of 7, 5 and 40%, and cysteine was added(total dietary cysteine contents:0.45%)to diet or not. The results are summarized as follow. Food intake, weight gain, food efficiency ratio, liver and kidney weights, femur weight and length of cadmium added group were lower than those of cadmium free group.
But, these were increased with increasing dietary protein level and cysteine addition. fecal cadmium excretion was remarkably increased in high protein(40%) groups. Thus, cadmium retention rates were decreased in high protein groups. Metallothionein concentrations in liver and kidney were increased in cysteine addition, and cadmium administration. Especially, these were remarkably increased in cadmium and cysteine added groups. Urinary calcium excretion was increased with cadmium administration, but urinary protein excretion and creatinine clearance were not changed in these animal. In conclusion, food intake, weight gain and organ weights were decreased with cadmium administration. Cadmium toxicity was alleviated by increasing dietary protein level and cysteine addition. High protein diet decreased cadmium retention by increasing fecal cadmium excretion, while cysteine addition increased metallothionein concentrations in liver and kidney. From these results, it was shown that cadmium toxicity was alliviated by synergistic effect of high protein level and cysteine addition.