- Overview
- Data/Specifications
- Literature/Support
- How It Works
- Related Products
Overview
PTH (Parathyroid hormone, Parathormone, Parathyrin) is biosynthesized in the parathyroid gland as a pre-proparathyroid hormone, a larger molecular precursor consisting of 115 amino acids. Following sequential intracellular cleavage of a 25-amino acid sequence, preproparathyroid hormone is converted to an intermediate, a 90-amino acid polypetide, proparathyroid hormone. With additional proteolytic modification, proparathyroid hormone is then converted to parathyroid hormone, an 84 amino acid polypeptide. In healthy individuals, regulation of parathyroid hormone secretion normally occurs via a negative feedback action of serum calcium on the parathyroid glands. Intact PTH is biologically active and clears very rapidly from the circulation with a half-life of less than four minutes. PTH undergoes proteolysis in the parathyroid glands, but mostly peripherally, particularly in the liver but also in the kidneys and bone, to give N-terminal fragments and longer lived C-terminal and midregion fragments. In subjects with renal insufficiency, C-terminal and midregion PTH assays typically give elevated PTH results, as reflected by impaired renal clearance.
Data/Specifications
Species: human
Sample Type:serum, plasma
Sample Size:25uL
Standard Curve Range: 7 - 700 pg/mL
Sensitivity: 0.9 pg/mL
Assay Length: 3.5 hrs
Literature/Support
Product Insert:
Intact PTH ELISA (product insert, PDF)
Articles/Troublshooting:
ELISA Troubleshooting Guide
ELISA Data Reduction Guide
References:
Bauer, J. M., Mikušová, L., Verlaan, S., Bautmans, I., Brandt, K., Donini, L. M., ... & Luiking, Y. (2020). Safety and tolerability of 6-month supplementation with a vitamin D, calcium and leucine-enriched whey protein medical nutrition drink in sarcopenic older adults. Aging Clinical and Experimental Research, 1-14.
Cashman, K. D., Kenny, S., Kerry, J. P., Leenhardt, F., & Arendt, E. K. (2019). ‘Low-salt’bread as an important component of a pragmatic reduced-salt diet for lowering blood pressure in adults with elevated blood pressure.Nutrients,11(8), 1725.
Jennings, A., Cashman, K. D., Gillings, R., Cassidy, A., Tang, J., Fraser, W., ... & Pietruszka, B. (2018). A Mediterranean-like dietary pattern with vitamin D3 (10 µg/d) supplements reduced the rate of bone loss in older Europeans with osteoporosis at baseline: results of a 1-y randomized controlled trial.The American journal of clinical nutrition,108(3), 633-640.
O"Callaghan, K. M., Hennessy, Á., Hull, G. L., Healy, K., Ritz, C., Kenny, L. C., ... & Kiely, M. E. (2018). Estimation of the maternal vitamin D intake that maintains circulating 25-hydroxyvitamin D in late gestation at a concentration sufficient to keep umbilical cord sera≥ 25–30 nmol/L: a dose-response, double-blind, randomized placebo-controlled trial in pregnant women at northern latitude.The American journal of clinical nutrition.
Hemmingway, A., Kenny, L. C., Malvisi, L., & Kiely, M. E. (2018). Exploring the concept of functional vitamin D deficiency in pregnancy: impact of the interaction between 25-hydroxyvitamin D and parathyroid hormone on perinatal outcomes.The American journal of clinical nutrition,108(4), 821-829.
Carson, E. L., Pourshahidi, L. K., Madigan, S. M., Baldrick, F. R., Kelly, M. G., Laird, E., ... & Mulhern, M. S. (2018). Vitamin D status is associated with muscle strength and quality of life in patients with COPD: a seasonal prospective observation study.International journal of chronic obstructive pulmonary disease,13, 2613.
Hayes, A., Duffy, S., O’Grady, M., Jakobsen, J., Galvin, K., Teahan-Dillon, J., ... & Seamans, K. M. (2016). Vitamin D–enhanced eggs are protective of wintertime serum 25-hydroxyvitamin D in a randomized controlled trial of adults, 2.The American journal of clinical nutrition,104(3), 629-637.
O"Donovan, C. B., Walsh, M. C., Nugent, A. P., McNulty, B., Walton, J., Flynn, A., & Brennan, L. (2015). Use of metabotyping for the delivery of personalised nutrition. Molecular nutrition & food research, 59(3), 377-385.
Cashman, K. D., Hayes, A., O"Donovan, S. M., Zhang, J. Y., Kinsella, M., Galvin, K., ... & Seamans, K. M. (2014). Dietary calcium does not interact with vitamin D3 in terms of determining the response and catabolism of serum 25-hydroxyvitamin D during winter in older adults. The American journal of clinical nutrition, 99(6), 1414-1423.
Wang, J., Trentham-Dietz, A., Hemming, J. D., Hedman, C. J., & Sprague, B. L. (2013). Serum factors and clinical characteristics associated with serum E-Screen activity. Cancer Epidemiology Biomarkers & Prevention, 22(5), 962-971.
Muldowney, S., Lucey, A. J., Hill, T. R., Seamans, K. M., Taylor, N., Wallace, J. M., ... & Kiely, M. (2012). Incremental cholecalciferol supplementation up to 15 μg/d throughout winter at 51–55 N has no effect on biomarkers of cardiovascular risk in healthy young and older adults. The Journal of nutrition, 142(8), 1519-1525.
Birmingham, D. J., Hebert, L. A., Song, H., Noonan, W. T., Rovin, B. H., Nagaraja, H. N., & Yu, C. Y. (2012). Evidence that abnormally large seasonal declines in vitamin D status may trigger SLE flare in non-African Americans. Lupus, 21(8), 855-864.
Cashman, K. D., Seamans, K. M., Lucey, A. J., Stöcklin, E., Weber, P., Kiely, M., & Hill, T. R. (2012). Relative effectiveness of oral 25-hydroxyvitamin D3 and vitamin D3 in raising wintertime serum 25-hydroxyvitamin D in older adults. The American journal of clinical nutrition, 95(6), 1350-1356.
Hill, T. R., Cotter, A. A., Mitchell, S., Boreham, C. A., Dubitzky, W., Murray, L., ... & Cashman, K. D. (2010). Vitamin D status and parathyroid hormone relationship in adolescents and its association with bone health parameters: analysis of the Northern Ireland Young Heart’s Project. Osteoporosis international, 21(4), 695-700.
Seamans, K. M., Hill, T. R., Wallace, J. M., Horigan, G., Lucey, A. J., Barnes, M. S., ... & Cashman, K. D. (2010). Cholecalciferol supplementation throughout winter does not affect markers of bone turnover in healthy young and elderly adults. The Journal of nutrition, 140(3), 454-460.
| References/Citations: | How the Intact PTH ELISA kit was used: |
| Cholecalciferol Supplementation throughout Winter Does Not Affect Markers of Bone Turnover in Healthy Young and Elderly Adults Kelly M. Seamans, et al., J. Nutr., Mar 2010; 140: 454 - 460. | The Intact PTH ELISA Kit was used to measure the concentration (ng/mL) of parathyroid hormone in adult human serum. |
| Estimation of the dietary requirement for vitamin D in free-living adults 64 y of age Kevin D Cashman et al.,Am. J. Clinical Nutrition, May 2009; 89: 1366 - 1374. | The Intact PTH ELISA Kit was used to measure the concentration (ng/mL) of parathyroid hormone in adult* human serum.*Adults greater than 64 years of age. |
Estimation of the dietary requirement for vitamin D in healthy adults Kevin D Cashman et al.,Am. J. Clinical Nutrition, Dec 2008; 88: 1535 - 1542. | The Intact PTH ELISA Kit was used to measure the concentration (ng/mL) of parathyroid hormone in adult* human serum.*Adults were age 20 to 40 years. |
| Low vitamin D status adversely affects bone health parameters in adolescents Kevin D Cashman et al.,Am. J. Clinical Nutrition, Apr 2008; 87: 1039 - 1044. | The Intact PTH ELISA Kit was used to measure the concentration (ng/mL) of parathyroid hormone in adolescent human serum. |
How It Works
The Intact PTH Immunoassay is a two-site ELISA (Enzyme-Linked Immunosorbent Assay) for the measurement of the biologically intact 84 amino acid chain of PTH. Two different goat polyclonal antibodies to human PTH have been purified by affinity chromatography to be specific for well defined regions on the PTH molecule. One antibody is prepared to bind only the mid-region and C-terminal PTH 39-84 and this antibody is biotinylated. The other antibody is prepared to bind only the N-terminal PTH 1-34 and this antibody is labeled with horseradish peroxidase (HRP) for detection.
Although mid-region and C-terminal fragments are bound by the biotinylated anti-PTH (39-84), only the intact PTH 1-84 forms the sandwich complex necessary for detection. The capacity of the biotinylated antibody and the streptavidin coated microwell both have been adjusted to exhibit negligible interference by inactive fragments, even at very elevated levels. In this assay, calibrators, controls, or patient samples are simultaneously incubated the enzyme labeled antibody and a biotin coupled antibody in a streptavidin-coated microplate well. At the end of the assay incubation, the microwell is washed to remove unbound components and the enzyme bound to the solid phase is incubated with the substrate tetramethylbenzidine (TMB). An acidic stopping solution is then added to stop the reaction and converts the color to yellow. The intensity of the yellow color is directly proportional to the concentration of intact PTH in the sample. A dose response curve of absorbance unit vs. concentration is generated using results obtained from the calibrators. Concentrations of intact PTH present in the controls and patient samples are determined directly from this curve.
