Tissue accumulation of lanthanum as compared to aluminum in rats with chronic renal failure--possible harmful effects after long-term exposure.

BACKGROUND

Lanthanum (La) carbonate is a new treatment for hyperphosphatemia. We tested the effects of oral La carbonate and aluminum hydroxide, respectively, on tissue accumulation and liver function in rats with chronic renal failure (CRF).

METHODS

Adult male non-CRF and CRF rats were randomly assigned to 3 groups receiving either standard diet (St.D), or the same diet supplemented with 3% La carbonate (non-CRF La vs. CRF La) or 3% aluminum hydroxide (non-CRF Al vs. CRF Al).

RESULTS

After 12 weeks, serum phosphorus was decreased in both CRF La and Al groups. Urinary La and Al excretion was increased in these two groups, and so was liver and bone La content, and liver Al content. Both total body and liver weight were decreased in CRF La and CRF Al rats. Liver cell proliferation was decreased in these groups, while plasma total alkaline phosphatases and alanine aminotransferase were increased. Hepatic total cytochrome p450 content was reduced in CRF La, but not in CRF Al rats.

CONCLUSION

Long-term oral La overload in rats with CRF was associated with a decrease in liver (and total body) weight and mild alterations of liver function, as was Al overload, possibly as a consequence of trace element accumulation.