HOME HELP CONTACT US SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Maccallum, S. H. Articles by Michell, R. H. Search for Related Content PubMed PubMed Citation Articles by Maccallum, S. H. Articles by Michell, R. H.

Some, though not all, previous studies have suggested that the inositol lipid which is hydrolysed during transmembrane signalling in response to receptor activation might be drawn from a metabolically discrete and relatively small hormone-sensitive lipid pool that turns over more rapidly than the bulk of membrane inositol lipid. In order to seek evidence for the existence of this putative hormone-sensitive lipid pool, we have double-labelled cells by growing them for 3 days in a medium containing [¹⁴C]inositol and then supplying them with [³H]inositol for the final 2 h before stimulation. We anticipated that stimulation of these doubly labelled cells might provoke the formation, from the postulated hormone-sensitive pool, of small quantities of relatively ³H-enriched inositol phosphates, and that these could be harvested from cells (provided that the cytosolic inositol monophosphatase and inositol 1,4-bisphosphate/inositol 1,3,4-trisphosphate 1-phosphatase activities are first inhibited by Li⁺). Experiments of this type, using both vasopressin-stimulated WRK1 rat mammary tumour cells and 3T3 mouse fibroblasts stimulated by prostaglandin F₂, have largely failed to demonstrate the formation of relatively ³H-enriched inositol phosphates. There was a tendency for phosphatidyl-inositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate to have slightly higher ³H: ¹⁴C ratios than phosphatidylinositol, but the ³H: ¹⁴C ratios of the inositol phosphates formed in stimulated cells were not substantially greater than the ³H: ¹⁴C ratios of the inositol lipids. We therefore conclude, at least for the two cell lines that we studied, that hormone-stimulated inositol lipid hydrolysis can call, either directly or indirectly, upon the majority of the inositol lipid complement of the stimulated cell.

Journal of Endocrinology (1989) 122, 379–389

This article has been cited by other articles:

				P. Varnai and T. Balla Visualization of Phosphoinositides That Bind Pleckstrin Homology Domains: Calcium- and Agonist-induced Dynamic Changes and Relationship to Myo-[3H]inositol-labeled Phosphoinositide Pools J. Cell Biol., October 19, 1998; 143(2): 501 - 510. [Abstract] [Full Text] [PDF]