The chromatographic separation of polyphosphoinositides and studies on their turnover in various tissues

Abstract

• 1.

  1. ³²P-labeled spots obtained when total lipid extracts from tissue slices are chromatographed on silicic acid-impregnated paper with phenol-ammonia as the developing solvent been characterized as di- and triphosphoinositide. This has enabled us to develop a simple, rapid, quantitative method for assaying the radioactivity incorporated into di- and triphosphoinositide in large numbers of small samples of tissue.

• 2.

  2. Slices of salts gland, brain cortex, kidney, liver, pancreas, and heart ventricle incorporated ³²P into di- and triphosphoinisitide when incubated in physiological saline containing [³²P]orthophosphate. With the exception of liver, the incorporation into triphosphoinositide was higher. The incorporation into diphosphoinositide generally paralled that into triphosphoinositide.

• 3.

  3. Under conditions in which ³²P incorporation into phosphatidic acid and phosphatidyl inositol was stimulated by acitylcholine in salt-gland slices, there was an inhibition of incorporation into the polyphosphoinositides.