ISSN:
1435-5604
Keywords:
Osteoblast
;
Parathyroid Hormone
;
Ins(1,4,5)P3
;
Cytosolic Ca2+
;
1,2 Diacylglycerol
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract The effects of parathyroid hormone (rat 1–34 fragment, rPTH) on phosphoinositide metabolism and intracellular Ca2+ mobilization were studied in a osteoblast-like clone MC3T3-E1 cells. rPTH caused a transient rise in intracellular Ca2+ in a dose-dependent manner. Significant Ca2+ increase was still observed under the extracellular Ca2+-free condition. In addition, 100nM rPTH stimulated rapid formation of both 1,2-diacylglycerol (1,2-DAG) and inositol 1,4,5-trisphosphate (Ins(1,4,5)P3), indicating agonist-triggered hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2). The current observations suggested that the rPTH-induced increase of intracellular Ca2+ was in part due to internal Ca2+ release mediated by Ins(1,4,5)P3. These results indicate possible involvement of phosphoiniositide metabolism in signal transduction of PTH-stimulated osteoblastic cells.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02374930
