Fig. 2: Relative steady-state levels of inositol, IPs and lipid PIns in cortical neurons cultured in various levels of inositol.

Neurons were grown for 5 days (D6–11) in various concentrations of inositol as shown, together with ³H-inositol (10 µCi/ml). Histograms show the cpm/well in fractions from SAX-HPLC analysis (see also Figure S2). Data were normalized for constant specific activity of ³H-inositol by dividing the cpm by 7.5 (for 40 μM inositol) and multiplying the cpm by 3.3 (for 1000 μM inositol). Therefore, the Y axis (adjusted cpm/well) indicate the cpm corrected for specific activity. Data shown are the mean and range from duplicate samples; the experiment was repeated with similar results. a Relative levels of cytosolic inositol and b relative levels of IPs_(1–4). c Same data as in (a, b) but shown on a log₁₀ scale. The ratios of each component at the different concentrations of inositol are indicated by the lines. d, e Relative levels of membrane PIns extracted from the same neurons used to generate data in (a), (b) and (c) shown on a linear (d) and a log₁₀ scale (e). The ratios of each component at the different concentrations of inositol are indicated by the lines as shown