Angiotensin-induced formation and metabolism of inositol polyphosphates in bovine adrenal glomerulosa cells

Abstract

The actions of angiotensin II (AII) on inositol polyphosphate production and metabolism were analyzed in cultured bovine adrenal glomerulosa cells. In cells labeled for 24 hr with [ 3H]inositol, AII caused a rapid and prominent rise in formation of Ins-P 3 (mainly the Ins-1,3,4,-P 3 isomer) and of Ins-P 4, with marked increases in two isomers of Ins-P 2 and Ins-P. These findings are consistent with rapid formation and turnover of Ins-1,4,5-P 3, partly via conversion to Ins-1,3,4,5-P 4 with subsequent metabolism to Ins-1,3,4-P 3 and lower inositol phosphates. The demonstration of a cytosolic Ins-P 3-kinase gave further evidence for the presence of the tris/tetrakisphosphate pathway and Ins-P 4 synthesis during AII action in the bovine adrenal cortex.