Summary Reasons for performing study: Parathyroid hormone (PTH) plays a critical role in the regulation of mineral metabolism in mammals. Until recently, the standard method for PTH measurement has been the 2nd generation intact‐PTH (I‐PTH) assay. Current evidence indicates that the I‐PTH assay binds to the PTH molecule and to an inactive N‐terminally truncated PTH fragment that tends to accumulate in the blood of uraemic patients. Therefore, a new 3rd generation PTH assay that detects only the whole PTH molecule (W‐PTH; cyclase‐activating PTH [CAP]) has been developed. Objectives: To validate this more specific W‐PTH assay for measurement of equine PTH and evaluate its clinical utility. Methods: W‐PTH and I‐PTH were measured in plasma samples from normal horses (adults and foals) and horses with nutritional secondary hyperparathyroidism (N2HPT) and with chronic renal failure (CRF). Replicate measurements and dilutional paralellism were used for assay validation. Changes in blood ionized calcium were induced by EDTA and CaCl2 administration. Results: Performance of the W‐PTH assay (accuracy, sensitivity, specificity and ability to detect changes in PTH in response to changes in calcium) was similar to that of the I‐PTH assay. Surprisingly, the relative W‐PTH concentration in normal horses and foals was higher than the relative I‐PTH concentration. W‐PTH values remained higher than I‐PTH during acute hypo‐ and hypercalcaemia. An increase in both W‐PTH and I‐PTH concentrations was found in horses with N2HPT. In horses with CRF, W‐PTH and I‐PTH values were very low and no increase in I‐PTH was observed. Conclusions: The W‐PTH assay can be used for measurement of equine PTH. Potential relevance: The use of W‐PTH assay is likely to improve the diagnosis of mineral metabolism in horses.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.