EFFECT OF STRONTIUM ADMINISTRATION ON BONES AND TEETH OF RATS MAINTAINED ON DIETS WITH DIFFERENT CALCIUM CONTENTS

In experiments on young rats with different levels of calcium intake it was found that rachitic changes in the bones and teeth developed when the diet contained very small amounts of calcium even though vitamin D was present in the food. When strontium was added to these diets more pronounced rickets developed. In animals receiving diets with a calcium content sufficient to prevent rickets, and also when the calcium intake was optimal, the addition of strontium resulted in rachitic changes. By increasing the calcium level of the diet with the strontium level kept constant these changes could be mitigated. Addition of strontium to the diet significantly depressed the blood calcium value in rats receiving low calcium diets when compared with controls on the same calcium intake. The blood phosphate remained unchanged. Animals with a low calcium intake and with strontium added to the diet, and which were given injections of calcium gluconate during the last 9 days of a 3 week period, exhibited healing rickets. In these animals the blood calcium level was significantly increased. The influence of addition of strontium to the diet on the blood calcium level is a fundamental factor in the development of strontium rickets but other effects have also to be considered, such as the influence of strontium on local factors in bone remodelling. © 1969 Springer-Verlag.