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Updated: May 23, 2026
03:57
Generation of Hypoparathyroid Rats via Carbon-Nanoparticle-Assisted Parathyroidectomy
Published on: July 14, 2023
Daily parathyroid hormone 1-34 replacement therapy for hypoparathyroidism induces marked changes in bone turnover and
Rachel I Gafni1, Jaime S Brahim, Panagiota Andreopoulou
1Skeletal Clinical Studies Unit, Craniofacial and Skeletal Diseases Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892-4320, USA. gafnir@mail.nih.gov
Summary
Parathyroid hormone (PTH) replacement therapy in hypoparathyroidism increased bone turnover and volume, particularly in cancellous bone. However, it led to decreased bone mineral density in some areas, especially in adolescents.
Area of Science:
- Endocrinology
- Bone Biology
- Metabolic Bone Disease
Background:
- Parathyroid hormone (PTH) has complex effects on bone, being catabolic long-term but anabolic intermittently.
- PTH deficiency is linked to reduced bone remodeling and increased bone mass.
- The skeletal effects of PTH replacement in hypoparathyroidism remain unclear.
Purpose of the Study:
- To investigate the impact of human PTH 1-34 (hPTH 1-34) therapy on bone in hypoparathyroid subjects.
- To assess changes in bone turnover, structure, and bone mineral density (BMD).
Main Methods:
- Five hypoparathyroid patients (2 adults, 3 adolescents) received daily hPTH 1-34 for 18 months.
- Calcitriol was discontinued; PTH doses were adjusted to maintain serum calcium.
- Bone markers, BMD, and iliac crest biopsies (pre- and post-treatment) were analyzed.
Main Results:
- hPTH 1-34 significantly elevated bone formation markers.
- Histomorphometry showed increased cancellous bone volume, trabecular number, and stimulated remodeling.
- Cortical porosity increased, while BMD Z-scores varied across skeletal sites, decreasing in total body and radius, especially in adolescents.
Conclusions:
- Daily hPTH 1-34 therapy stimulates bone turnover and increases cancellous bone volume in hypoparathyroidism.
- Treatment alters bone structure, increasing trabecularization and cortical porosity.
- Skeletal compartment-specific effects and potential risks, particularly in growing adolescents, warrant further investigation.
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