Bone metabolism in a mutant strain of rats which lack bone resorption

¹ Departments of Medicine and Biochemistry, Harvard Medical School, Boston, Massachusetts

The metabolism in vitro of Ca, P, glycine, glucose, O₂, and citrate by bone from normal rats and their littermates who suffered from a generalized defect in bone resorption (incisorless animals (ia)) have been compared. Defects in the oxidative metabolism of glucose and glycine and in the rate of O₂ consumption have been found in bone from ia animals. Further, this defect has been traced to a partial block in the oxidation of citrate to -ketoglutarate that could account for many of the phenomena observed. Bone from ia animals has also been found to maintain a higher concentration of Ca in its incubation medium at steady state than bone from normals. This phenomenon has been shown to be entirely the result of increases in the fraction of the total Ca concentration which depends on cellular metabolism and not to result from changes in the solubility of the bone mineral. Possible relationships between the cellular oxidative defect and the changes in Ca distribution in vitro have been examined in light of present knowledge.

Note:
With the Technical Assistance of Sylvia M. Zottu and Gretchen Lange