Fig. 3.
Furosemide changed the reversal potential of sIPSCs. A, Spontaneous IPSCs were inward and outward atVH of −61 mV. Furosemide (furo; 0.1 mm) increased the frequency and amplitude of inward sIPSCs (recorded in 2 mm[K+]o, 15 mm[A−]pip), whereas outward sIPSCs disappeared. The onset of the furosemide effect is already seen after 10 sec, and the effect is reversible. Letters mark time points that are shown at higher sweep speed in the lower traces.B, In another cell under otherwise identical recording conditions as in A, VH was set to record outward sIPSCs. Application of increasing concentrations of furosemide first reduced the amplitude of outward sIPSCs and then reversed sign of sIPSCs.