The effect of vitamin D3 and dietary calcium level on the cadmium-induced morphological and biochemical changes in rat intestinal mucosa.

The effect of vitamin D3 and dietary calcium level on the cadmium-induced changes was observed in the duodena of rats raised on various diets differing in vitamin D and calcium levels. Observation with scanning electron microscopy revealed that vitamin D and dietary calcium were required for normal intestinal villi and microvilli formation. The damaged cells were observed in the intestinal villi of cadmium-exposed rats. Furthermore, dietary cadmium reduced the enzyme activities in microvilli. Especially, alkaline phosphatase activity was reduced in the cadmium-exposed groups, even though it was still responsive to vitamin D3. These effects with cadmium were modulated by vitamin D3 and dietary calcium level. That is, in the presence of vitamin D3 and calcium, the effect of cadmium on intestinal villi and microvilli was reduced.