Two-site assay of intact parathyroid hormone in primary hyperparathyroidism: studies in basal conditions, following adenoma removal and during calcium and EDTA infusion

Gianfranco Mazzuoli, Salvatore Minisola, Liliana Scarnecchia, Maria Teresa Pacitti, Vincenzo Carnevale, Elisabetta Romagnoli, Flavio Bigi, Giuseppe Bianchi

Research output: Contribution to journalArticle

Abstract

This study has been carried out in order to investigate parathyroid hormone secretion in patients with primary hyperparathyroidism in basal conditions, during stimulation and suppression tests and following successful surgery. Parathyroid gland secretory activity has been evaluated by a highly sensitive immunoradiometric assay (IRMA) which detects only the biologically intact active hormone and with a well established midmolecule (MM) PTH RIA. There was a good correlation between the two assays in basal state (r = 0.779); however the correlation found between serum PTH levels and total calcium values was better for the intact hormone (P <0.001) than for the radioimmunoassay (P <0.05). Twenty-four hours following surgery, serum intact PTH levels were in all patients <10 pg/ml while midmolecule PTH was still detectable, thereafter remaining at a higher level during the next six days. Serum IRMA PTH levels fell rapidly in response to the increase in serum calcium, then there was a trend to reach a plateau; serum midregion PTH levels fell, although slower than those of intact hormone. The percent increase obtained for serum intact hormone levels was higher than that observed for MM RIA, following EDTA stimulation. The results obtained indicate that the assays of intact and midmolecule parathyroid hormone clearly reflect different aspects of hormone metabolism 'in vivo' and may prove therefore to be useful for its investigation in various calcium disorders.

Original languageEnglish
Pages (from-to)239-248
Number of pages10
JournalClinica Chimica Acta
Volume190
Issue number3
DOIs
Publication statusPublished - Oct 15 1990

Keywords

  • Calcium
  • Hyperparathyroidism
  • Parathyroid hormone

ASJC Scopus subject areas

  • Biochemistry
  • Clinical Biochemistry

Fingerprint Dive into the research topics of 'Two-site assay of intact parathyroid hormone in primary hyperparathyroidism: studies in basal conditions, following adenoma removal and during calcium and EDTA infusion'. Together they form a unique fingerprint.

  • Cite this