The noncalcemic analogue of vitamin D, 22-oxacalcitriol, suppresses parathyroid hormone synthesis and secretion.

Abstract

OCT, a non-calcemic analogue of 1,25(OH)2D3 has been found to have a more potent activity than that of 1,25(OH)2D3 regarding cell differentiation and immunopotentiation activity, and to prolong the average life span of MRL/l mice. Recently, we found that OCT effectively suppressed the secretion and synthesis of PTH without inducing hypercalcemia. In primary cultures of bovine parathyroid cells, OCT was capable of suppressing PTH release in a dose-dependent manner. OCT was also active in vivo, and, like 1,25(OH)2D3, decreased the pre-pro(PTH) mRNA levels. In a group of rats with CRF, daily administration of OCT, 8 ng i.p. for 2 weeks returned PTH levels to normal without changes in serum calcium. Preliminary results in dogs with CRF indicated that after the administration of OCT 5 micrograms i.v., N-terminal PTH decreased by 76% without changes in Ca. In conclusion, OCT may provide a unique contribution to the treatment of secondary hyperparathyroidism.

• Authors: Y Nishii, J Abe, T Mori, A J Brown, A S Dusso, J Finch, S Lopez-Hilker, J Morrissey, E Slatopolsky
• Journal: Contributions to nephrology (Contrib Nephrol) Vol. 91 Pg. 123-8 ( 1991) ISSN: 0302-5144 [Print] Switzerland
• PMID: 1800003 (Publication Type: Journal Article, Review)

Chemical References

• Parathyroid Hormone
• Calcitriol
• maxacalcitol

Topics

• Animals
• Calcitriol (analogs & derivatives, metabolism, pharmacology)
• Cells, Cultured
• Humans
• Parathyroid Hormone (biosynthesis, metabolism)