D4 reduction of GABAAR currents is through an
actin-dependent mechanism. A, plot of normalized peak
GABAAR current as a function of time and PD168077 (30
μm) application in neurons dialyzed with or without the dynamin
inhibitory peptide (50 μm). Inset, representative
current traces (at time points denoted by #). Scale bar, 500 pA, 1 s.
B, cumulative data (means ± S.E.) showing the percentage of
reduction of GABAAR current by PD168077 in a sample of neurons in
the absence (control) or presence of the dynamin inhibitory peptide.
C, plot of normalized peak GABAAR current as a function of
time and PD168077 application in neurons dialyzed with the actin stabilizer
phalloidin (12.5 μm). Inset, representative current
traces (at time points denoted by #). Scale bar, 500 pA, 1 s.
D, cumulative data (mean ± S.E.) showing the percent reduction
of GABAAR current by PD168077 in the absence or presence of
phalloidin in a sample of neurons tested. *, p < 0.005, ANOVA.
E, plot of normalized peak GABAAR current as a function of
time and PD168077 application in neurons dialyzed with the actin depolymerizer
latrunculin B (5 μm) or perfused with the microtubule
depolymerizer colchicine (30 μm). F, cumulative data
(mean ± S.E.) showing the percent reduction of GABAAR
current by PD168077 in the absence or presence of latrunculin B or colchicine
in a sample of neurons tested. *, p < 0.005, ANOVA. G,
plot of evoked IPSC as a function of time and PD168077 application in a PFC
slice perfused with latrunculin B. Inset, representative IPSC traces
(at time points denoted by #). Scale bar, 50 pA, 20 ms. ctl,
control; PD, PD168077; Dyn. inh. pep., dynamin inhibitory
peptide; Lat, latrunculin B; Col, colchicine.