These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Human parathyroid hormone-related peptide-(107-111) does not inhibit bone resorption in neonatal mouse calvariae. Author: Sone T, Kohno H, Kikuchi H, Ikeda T, Kasai R, Kikuchi Y, Takeuchi R, Konishi J, Shigeno C. Journal: Endocrinology; 1992 Dec; 131(6):2742-6. PubMed ID: 1306984. Abstract: Recent analysis of the structure-function relationship of human PTH-related peptide (hPTHrP) has led to the discovery that its direct inhibitory activity on osteoclastic bone resorption resides fully in the 107-111 sequence of the peptide, as assessed by a bone resorption assay using isolated rat osteoclasts. Here we report that hPTHrP-(107-111) is inactive in neonatal mouse calvariae in culture. hPTHrP-(107-111), at doses of 10(-12)-10(-6) M and incubation periods up to 96 h, did not affect either basal or agonist-stimulated 45Ca release from prelabeled neonatal mouse calvariae, while salmon calcitonin was a potent and powerful inhibitor of both basal and stimulated 45Ca release from bone. Moreover, salmon calcitonin, but not hPTHrP-(107-111), inhibited the increase in osteoclast number in hPTHrP-(1-34)-treated bones. Furthermore, hPTHrP-(107-139) also failed to inhibit 45Ca release and the hPTHrP-(1-34)-induced increase in osteoclast number in this organ culture model when tested under conditions identical to those for hPTHrP-(107-111). The addition of indomethacin to hPTHrP-(107-111)- or hPTHrP-(107-139)-treated bones was without effect, excluding the possibility that the direct inhibitory activity of these peptides on osteoclasts is ablated by a prostaglandin-mediated mechanism. Although the mechanism underlying the apparent inability of the carboxyl-terminal PTHrP fragments to inhibit osteoclastic bone resorption in neonatal mouse calvariae is unknown, it may involve the complex microenvironment of osteoclasts in intact bone, which contains a large variety of cell types other than osteoclasts.[Abstract] [Full Text] [Related] [New Search]