Radioimmunoassay of calcitonin in normal human plasma: problems, perspectives and prospects.

Radioimmunoassay of calcitonin in normal human plasma is hindered by immunochemical heterogeneity in plasma, variable susceptibility of antisera to non-specific factors, limited assay sensitivity, and other problems. Many controversial points in the literature arise from these difficulties. Measurement of calcitonin after various extraction procedures yields greater consistency of results. Recent advances in calcitonin assay technology offer the promise of measuring calcitonin monomer with sufficient sensitivity to permit studies of normal calcitonin physiology and of the hormone's role in human disease.