Intra-Individual Variation in Serum Type I Procollagen Carboxy-Terminal Propeptide and Type I Collagen Carboxy-Terminal Cross-Linked Telopeptide Concentrations

作者：H P Stevenson, Hilary Leslie, Brian L. Sheridan · 发表于：Annals of Clinical Biochemistry International Journal of Laboratory Medicine · 年份：1997 · DOI：10.1177/000456329703400316 · 被引用次数：14 · 研究领域：Clinical Laboratory Practices and Quality Control、Bone health and treatments、TGF-β signaling in diseases

Formation of type I collagen from procollagen causes release of propeptides which can be detected in serum. Measurement of the procollagen carboxy-terminal pro peptide (PICP) by radioimmunoassay has shown that serum levels correlate with the rate of bone formation, and increased concentrations have been reported in skeletal growth, Paget's disease and bone metastases.l? The carboxy-terminal telopeptide of type I collagen (ICTP) is released on collagen degradation and has been quantitated in serum by radioimmunoassay as a putative marker of bone resorption ..1 Significant increases in ICTP levels have been found in patients with skeletal growth, rheumatoid arthritis, metastatic bone lesions or renal impairment. Although the extent of normal physiological variation in serum PICP and ICTP within individuals is not clear, significant changes in PICP and/or ICTP levels have been observed in response to various treatments. The result of any biochemical analysis is generally reported as a single value which is an estimate of the homeostatic set-point, and has an associated variance, the intra-individual variance, with analytical and biological components. A reference interval may be determined using samples from normal individuals but, when the intra-individual variance is lower than the inter-individual variance, serial comparison of values within an individual may be more useful than comparison with a reference interval. Since serum levels of PICP and ICTP may be genetically deter...