Figure 6. Modulation of hypertonic induction of amino acid transport activity and accumulation of NPS.

Initial rates of cell uptake of 2-[1-¹⁴C]methylaminoisobutyric acid (MeAIB) (A) and cell contents of ninhydrin-positive solutes (NPS) (B) were measured after the cells had been incubated for the indicated times in depleted hypertonic (0.5 osmol (kg H₂O)⁻¹) medium with or without added betaine and myo-inositol, each at 0.1 mmol l⁻¹. The extracellular concentration of MeAIB was 0.1 mmol l⁻¹. Mean values (±s.d.) of four measurements are given. ○, depleted of compatible osmolytes; •, with betaine and myo-inositol.