title: A study on the biological significance of midregion and intact parathyroid hormone in hemodialysis patients.
abstract: In this study, we investigated the relationship between the concentrations of intact parathyroid hormone (i-PTH) and midregion PTH (m-PTH) measured by an immunoradiometric assay and a radioimmunoassay, respectively, versus various demographic and biochemical parameters, bone mineral density (BMD) of the lumbar spine (LS) and radius, and the radiographic findings of osteosclerosis and aortic calcification in hemodialysis (HD) patients. m-PTH correlated positively and more significantly with serum calcium (Ca), serum phosphorus (P), Ca-P solubility products (Ca x P) and LS-BMD than i-PTH did (P = 0.024 vs. 0.531, 0.001 vs. 0.061, 0.0001 vs. 0.125, and 0.017 vs. 0.284, respectively). A positive correlation between the percent changes in serum P over the 1-month measurement period and those in m-PTH rather than in i-PTH was also observed (P = 0.021 vs. 0.869). These data indicate than m-PTH is distinct from i-PTH in its positive correlation with serum Ca, serum P, Ca [symbol: see text] P and LS-BMD in HD patients. Since m-PTH is known to consist mostly of the midregion and carboxyl-terminal fragments of PTH in HD patients, the present study suggests that these PTH fragments may be biologically significant in the patients in vivo.
authors.affiliation: Hattori Hospital, Hyogo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: S
authors.initials: S
authors.lastname: Hattori
authors.forename: M
authors.initials: M
authors.lastname: Nakai
authors.forename: K
authors.initials: K
authors.lastname: Sekita
authors.forename: Y
authors.initials: Y
authors.lastname: Fujita
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001012:Aorta, Abdominal / Q000000981:diagnostic imaging; D015519:Bone Density; D002114:Calcinosis / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D015592:Immunoradiometric Assay; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D010026:Osteosclerosis / Q000000981:diagnostic imaging / Q000378:metabolism; D010281:Parathyroid Hormone / Q000097:blood* / Q000502:physiology*; D010446:Peptide Fragments / Q000097:blood* / Q000502:physiology*; D011859:Radiography; D006435:Renal Dialysis
chemical_list: D010281:Parathyroid Hormone; D010446:Peptide Fragments