EFFECT OF SHORT TERM ALPHA IRRADIATION ON PARATHYROID ACTIVITY AND OSTEOCLAST NUMBERS.

Summary A study of the distribution of plutonium-239 in bone, and its effects on bone cells has been presented and correlated with endogenous parathyroid activity. There was no measurable effect on the function of existing osteoblasts or osteoclasts during this short term (5 day) experiment. Also, incorporation of plutonium into osteoclasts did not disrupt the ability of parathyroid hormone to maintain normal calcium levels. However, it could be demonstrated that plutonium, for the first 48 hours after administration, affected certain of the undifferentiated bone cells, which in turn prevented the increased osteoclast production normally seen following endogenous parathyroid stimulation.