[The blood calcium error induced by oral calcium loading: study of the homeostatic compensation mechanism]

The oral calcium load test, originally proposed for evaluating the intestinal calcium absorption and the renal calcium leak triggers some endocrine and metabolic responses addressed to correct the "calcemic error" induced by the load. Besides the increased plasma calcium there are: plasma PTH drop, increment in the urinary calcium excretion and in the threshold of tubular phosphate reabsorption. These responses have been measured and reciprocally correlated in 9 young adults at different times after the oral calcium load. The responses can be assessed with high precision in clinical practice and are in agreement with the known physiological models. The oral calcium load test is proposed as a tool for studying in the osteopenic population in the individual's capacity of correcting the calcemic error induced by the load.