Human synthetic calcitonin gene-related peptide inhibits bone resorption in vitro

S. M. D’Souza, I. Macintyre, S. I. Girgis, G. R. Mundy

Research output: Contribution to journalArticlepeer-review

83 Scopus citations


The calcitonin gene-related peptide (CGRP) is a pepticle which normally circulates. It is encoded by the calcitonin gene, whose precise function is unknown. Since it has recently been shown that human CGRP (hCGRP) lowers plasma calcium levels in both the rat and the rabbit, we examined the in vitro effects of human synthetic CGRP on bone resorption (as measured by 45Ca release) stimulated by PTH, prostaglandin E2, and 1,25-dihydroxyvitamin D3. CGRP caused a dose-dependent inhibition of PTH-stimulated resorption, with 50% inhibition at approximately 5 × 10−8 M CGRP. The inhibitory effects of CGRP on PTH-mediated bone resorption were not due to toxic effects, since bones preincubated with CGRP for 48 h were subsequently able to respond to PTH. The inhibitory activity of CGRP in the rat was approximately 3 orders of magnitude less potent than that of human calcitonin. In contrast to the effects of calcitonin, a marked inhibition of PTH-stimulated bone resorption was still observed after 96 h in the continued presence of CGRP. CGRP (10−6-10−8 M) also inhibited resorption stimulated by prostaglandin and 1,25-dihydroxyvitamin D3 in a dosedependent manner, but had no significant effect on basal bone resorption. In conclusion, these data show that hCGRP inhibits hormone-stimulated bone resorption in vitro. Although it is less potent than calcitonin in the rat, CGRP has been shown to have potency comparable to that of calcitonin in other species, and therefore, a role for CGRP as a therapeutic agent in states of increased bone resorption cannot be ruled out.

Original languageEnglish (US)
Pages (from-to)58-61
Number of pages4
Issue number1
StatePublished - Jul 1986

ASJC Scopus subject areas

  • Endocrinology


Dive into the research topics of 'Human synthetic calcitonin gene-related peptide inhibits bone resorption in vitro'. Together they form a unique fingerprint.

Cite this