PARATHYROID FUNCTION AND BONE METABOLIC MARKERS IN PRIMARY AND SECONDARY HYPERPARATHYROIDISM

Remarkable changes of parathyroid function immediately after parathyro idectomy were evaluated in primary (PHPT) and secondary (RHPT) hyperpa rathyroidism. Bone metabolism was also evaluated by new specific marke rs of bone formation and resorption. A rapid decline into the undetect able range, and a rapid recovery of serum bioactive parathyroid hormon e (PTH) concentrations were observed after parathyroidectomy in PHPT. Since the function of the remnant parathyroid glands was not clear, we investigated the transcription of PTH mRNA. Despite the suppression o f PTH secretion in the remnant parathyroid glands, no significant diff erence was found in the amount of PTH mRNA present in an adenoma as co mpared to a remnant gland when evaluated by cytoplasmic dot hybridizat ion and in situ hybridization. Although measurement of serum PTH conce ntration by assays of inactive fragment was available for the longterm follow-up of PTH function in RHPT, parathyroid function should be eva luated by biologically active intact PTH immediately after operation. The PTH gradient also was successfully evaluated by the measurement of intact PTH. A discrepancy was observed between bone resorption evalua ted by type I collagen cross-linked N-telopeptide as compared to bone formation evaluated by osteocalcin immediately after operation. This d iscrepancy will improve and bone mineral density will increase in the first 6 months after parathyroidectomy. (C) 1997 Wiley-Liss, Inc.