Effects of atropine and mecamylamine on the membrane potential and conductance changes produced by 5-methylfurmethiodide (MFI). A) Thirty µM atropine has a small but significant effect on the depolarizing responses to 100 µM MFI. Representative trace and bar chart (n = 8). Control, 9.8 ± 0.8 mV; + atropine, 7.4 ± 0.8 mV. B) Thirty µM mecamylamine reduces, but does not completely block, depolarizing responses to 100 µM MFI. Representative trace and bar chart (n = 4). Control, 6.5 ± 1.0 mV; + mecamylamine, 3.3 ± 1.0 mV.