A comparative study of blood chemistry in bone marrow and peripheral blood

This study was undertaken to obtain baseline data on electrolyte composition of bone marrow blood and compare it with those of simultaneously obtained peripheral blood in order to assess the clinical usefulness of bone marrow blood as an indicator of the early changes of bone mineral metabolism. The mineral salts deposited in the skeleton are not in chemical equilibrium with the circulating blood (Ramp and Neuman), and while the local concentration in bone lesions might thus be high, after dilution into the entire circulating volume, the total amount of enzyme might be too small to cause changes in the peripheral blood readings. And even when no tissue is obtained, the bone blood from the lesion may provide useful information(Woodard and Marcove). In the animal experimental group, electrolyte composition of femoral bone marrow blood was compared with a simultaneously obtained peripheral blood from the abdominal aorta of six week old Long Evans male rats with normal and calcium deficient diets. In the human group, 10 ml of bone marrow blood was obtained from the iliac donor site at the time of bone grafting for spondylolysis, spondylolisthesis and lumbar disc herniation and 10 ml of peripheral blood. was obtained from the cephalic vein immediately before the bone grafting. Electrolyte and enzyme composition of bone marrow blood from bone tumor sites was compared with peripheral blood and also with that obtained from the bone grafting(control) group. The results obtained are as follows.; 1. The concentration of total and ionized calcium in the bone marrow blood was significantly lower and inorganic phosphorus was significantly higher than values obtained from the peripheral blood of rats fed with normal and calcium deficient diets. 2. Similar differences were demonstrated in the human bone marrow blood and peripheral blood obtained from the bone grafting group. A modertae excess of alkaline phosphatase was found in the bone marrow blood. 3. A large excess of alkaline phosphatase was found in the bone marrow blood obtained from bone tumor.