Fig. 1. IGF-I rescues SHEP cells from hyperosmotic-induced apoptosis via PI-3K. In A, serum-deprived SHEP cells are incubated with DMEM (D) ± 100 nM WTM or 300 mM mannitol (H) ± 10 nM IGF-I (I) ± 100 nM WTM. Cells exposed to conditions with WTM are pretreated with WTM for 1 h before the addition of experimental conditions. WTM is replenished every 6 h, and IGF-I is replenished every 12 h. After 24 h, cells are collected and prepared for flow cytometry. The percentage of apoptotic cells represents the percentage of DNA in the sub-G0 population as measured by propidium iodide staining for flow cytometry. In B, serum-deprived SHEP cells were exposed to DMEM (D) ± 10 µM PD98059 (PD) or 300 mM mannitol (H) ± 10 nM IGF-I (I) ± 10 µM PD. Cells exposed to PD are pretreated with the inhibitor for 1 h before the addition of experimental conditions. After 24 h, cells are prepared for flow cytometry. For both A and B, * = P < 0.01 compared with DMEM and ** = P < 0.01 compared with 300 mM mannitol.