Neurotransmitter-caused increase in [3H]inositol incorporation into phosphatidylinositol de novo synthesis vs exchange.
[3H]inositol and 32Pi were simultaneously incorporated into rat parotid phosphatidylinositol. The ratio of [3H]/32Pi incorporation dropped dramatically following stimulation with muscarinic or alpha-adrenergic agonists and returned to control values following the addition of appropriate antagonists. The drop in [3H]/32Pi ratio can be explained by a rapid increase in de- novo synthesis of phosphatidylinositol following its receptor-mediated breakdown. The change in this ratio also provided evidence for the existence of CDP-DG + inositol in equilibrium phosphatidylinositol exchange reaction in the intact tissue.
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002217:Carbachol / Q000494:pharmacology; D004837:Epinephrine / Q000494:pharmacology; D007294:Inositol / Q000378:metabolism*; D010306:Parotid Gland / Q000187:drug effects / Q000378:metabolism*; D010646:Phentolamine / Q000494:pharmacology; D010710:Phosphates / Q000378:metabolism; D010716:Phosphatidylinositols / Q000378:metabolism*; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D011942:Receptors, Adrenergic, alpha / Q000502:physiology*; D011976:Receptors, Muscarinic / Q000502:physiology*
D010710:Phosphates; D010716:Phosphatidylinositols; D011942:Receptors, Adrenergic, alpha; D011976:Receptors, Muscarinic; D007294:Inositol; D001285:Atropine; D002217:Carbachol; D011433:Propranolol; D004837:Epinephrine; D010646:Phentolamine