title: Tetraenoic species are conserved in muscarinically enhanced inositide turnover.
abstract: Carbamylcholine enhances the labeling of phosphatidate and phosphatidylinositol from 32Pi in nerve endings. Approximately 74% of labeled phosphatidate and 85% of labeled phosphatidylinositol produced on muscarinic stimulation are accounted for by tetraenoic species, as detected by argentation TLC. Incubation of membranes derived from nerve endings with [gamma-32P]ATP under conditions of phosphodiesteratic degradation of endogenous polyphosphoinositides resulted in increased labeling of phosphatidate. Approximately 78% of the newly formed phosphatidate was in a tetraenoic fraction. It is concluded that in muscarinically stimulated nerve endings, the diacylglycerol moiety is conserved following diacylglycerol release from polyphosphoinositides through its resynthesis to inositol lipid via phosphatidate.
authors.forename: L A
authors.initials: LA
authors.lastname: Van Rooijen
authors.forename: A K
authors.initials: AK
authors.lastname: Hajra
authors.forename: B W
authors.initials: BW
authors.lastname: Agranoff
mesh_terms: D000818:Animals; D002217:Carbachol / Q000494:pharmacology; D002540:Cerebral Cortex / Q000378:metabolism; D004075:Diglycerides / Q000378:metabolism; D006168:Guinea Pigs; D007295:Inositol Phosphates / Q000378:metabolism; D009411:Nerve Endings / Q000378:metabolism*; D010712:Phosphatidic Acids / Q000378:metabolism; D019269:Phosphatidylinositol 4,5-Diphosphate; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols / Q000378:metabolism*; D011976:Receptors, Muscarinic / Q000187:drug effects / Q000502:physiology*
chemical_list: D004075:Diglycerides; D007295:Inositol Phosphates; D010712:Phosphatidic Acids; D019269:Phosphatidylinositol 4,5-Diphosphate; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols; D011976:Receptors, Muscarinic; C037178:phosphatidylinositol 4-phosphate; D002217:Carbachol