W1659 Peroxynitrite Inhibits Na-Glucose Co-Transport But Not Na/H Exchange in IEC-18 Cells

W1659

of mouse proximal tubules using forskolin and A23187, agents that inhibit Nhe3 activity and short term dexamethasone treatment an agent that causes acute stimulation of Nhe3 activity. Intracellular pH, monitored by SNARF4, was measured according to Murtazina et al J. Biol. Chem. 282(34): 25141, 2007. Thin slices of mouse kidney cortex were superfused, acidified by NH4 then exposed to TMA or Na and initial rates of alkalization were measured in delta pH/min. HOE 694 was added to inhibit Nhe1 and Nhe2 activity. When forskolin and A23187 were applied to wt and Clcn5 ko mouse tubules both groups had inhibition of NHe3 activity but there was no difference between wt and Clcn5 ko. When short tern dexamethasone was given, wt mouse proximal tubules showed an increase in Nhe3 activity from 0.29±0.02 to 0.39±0.03, p