Fig. 1.

(A) Representative traces of wild-type hGABA-A ρ1 receptor currents generated by coapplication of GABA EC₅₀ (10 μM) with increasing concentrations of amiloride (Amil). (B) Potentiating amiloride concentration-response profile is shown. Data represents the mean ± S.E.M. of 10 μM GABA and coapplication of increasing amiloride 1, 3, 10, 30, 100, 300, and 1000 μM) of n ≥ 4 individual cells. The amiloride EC₅₀ was 77.0 ± 6.3 µM with a Hill coefficient of 1.6 ± 0.2. (C) GABA concentration-response profiles in the absence and presence of amiloride are shown. A leftward shift of the GABA EC₅₀ is depicted from the GABA EC₅₀ (9.4 ± 0.1 μM GABA, control), 30 μM amiloride (7.8 ± 0.5 μM GABA), 100 μM (6.4 ± 0.6 μM GABA), 300 μM (5.9 ± 0.9 μM GABA) (Table 1). Each recording was normalized to the cell’s maximal response (1 mM GABA).