Fig. 6.

The furosemide-sensitive K⁺–Cl⁻ cotransporter extruded or accumulated Cl⁻ depending on [K⁺]_o and [Cl⁻]_i. A, The shift of dendritic E_GABA induced by furosemide was larger in 2 mm [K⁺]_o than in 10 mm [K⁺]_o when [A⁻]_pip was high (15 mm).A1, Elevating [K⁺]_ofrom 2 to 10 mm shifted E_GABA of dendritic I_GABA (▴ marks application of GABA) to positive values, which resulted in a reversal of current direction (V_H is indicated below chart records). Washout of furosemide had only a small effect onI_GABA in 10 mm[K⁺]_o (A2) but a strong effect in 2 mm [K⁺]_o.A4, Current–voltage relationship for the cell shown inA1–A3. For clarity, control and recovery data were pooled. Arrows indicate direction of the shift in dendritic E_GABA. B, In another cell recorded with low [A⁻]_pip (4.5 mm), furosemide induced a small positive shift at 2 mm[K⁺]_o but a small negative shift of dendritic E_GABA at 10 mm[K⁺]_o.