Osmotic stress-induced PtdIns(4,5)P2 production in Arabidopsis plants. Anion-exchange HPLC analysis of deacylated myo-[2-3H]inositol-labeled lipids from plants that were untreated (A, B, and C, ×) or treated with 0.25 m NaCl (A, ●), 0.25 m KCl (B, ▴), and 0.5 m sorbitol (C, ♦) for 30 min. The total counts in each sample were 7 × 105.