Figure 8.
Inhibition of PI3-kinase prevents effect of insulin on ENaC activity in mpkCCDc14 cells. Pretreatment with LY29004, a PI3-kinase inhibitor, prevents ability of insulin to increase ENaC activity in mpkCCDc14 cell monolayer. Cells were serum starved overnight, and measurements were performed as described in Materials and Methods. Insulin (20 nM) was added basolaterally at time 0. Cells were pretreated with 10 μM of LY294002 or LY303511 (inactive negative control compound for LY29004) 30 min before the application of insulin or vehicle. Amiloride (10 μM) was added to the apical membrane at the end of experiment.