Kinetics of protein-mediated transfer of rat pancreatic microsomal phosphatidylinositol to liposomes.
Pancreatic microsomes were isolated from fasted and pilocarpine-injected rats and the microsomal phosphatidylinositol radiolabelled with myo-[2-3H]inositol by isotopic exchange. A standard reaction mixture was established in which partially purified rat liver phosphatidylinositol exchange proteins sustain a maximal rate of phosphatidylinositol transfer from rat pancreatic microsomes to liposomes. Determination of the transfer kinetics shows (1) that pancreatic microsomal phosphatidylinositol is partitioned approximately equally between a non-exchangeable and a single exchangeable pool and (2) that cholinergic stimulation does not significantly change the relative sizes of the two pools nor the exchange half-life of the latter pool.
D000818:Animals; D006207:Half-Life; D007700:Kinetics; D008081:Liposomes / Q000378:metabolism*; D008861:Microsomes / Q000378:metabolism*; D010179:Pancreas / Q000378:metabolism*; D010716:Phosphatidylinositols / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D008081:Liposomes; D010716:Phosphatidylinositols; D011506:Proteins