Picrotoxin enhanced hippocampal fEPSPs were disrupted by suprafusion of bumetanide in a dose dependent manner.

(A) From Left to right, representative traces of fEPSPs recorded extracellularlly under control condition, after exposure to 10 µM picrotoxin (PTX), PTX + 5 µM bumetanide (BUT), and PTX + 10 µM BUT. Application of 10 µM PTX significant enhanced fEPSP amplitude in hippocampus CA1 Schaffer collateral fiber (178±8%, ***p<0.001 compared with control fEPSP). The picrotoxin enhanced fEPSPs were attenuated by bumetanide treatment in dose dependent manner (5 µM bumetanide: 149±10%, P = 0.066 compared with PTX group; 10 µM bumetanide: 117±9%, ***p<0.001 compared with PTX group, P = 0.453 compared with control group).