Hypervitaminosis D in New World Monkeys

Hypervitaminosis D was produced in squirrel monkeys (Saimiri sciureus) and Cebus monkeys (Cebus albifrons) by daily oral administration of 50,000–100,000 IU vitamin D3/day. Similar doses of vitamin D2 did not induce detectable toxicity. The syndrome in the squirrel monkey was characterized by hypercalcemia, hyperphosphatemia, uremia, and death in the absence of significant metastatic calcification or microscopic renal lesions. The Cebus monkeys developed widespread metastatic calcification similar to that reported in other species. Lesions of bone were not seen in either species. These data further support the difference in activities between vitamins D2 and D3 in New World primates and also suggest that the lesions of vitamin D toxicity may vary with dose and duration of illness. The data also indicate that renal failure in this syndrome need not be related to nephrocalcinosis but may represent a direct effect of vitamin D on renal function.