Current and fluorescence responses from the ρ1 receptor labeled
with A5m at the S66C site. Current and fluorescence responses from receptors
activated by 5 μM GABA in the absence and presence of 20
μM 3α5βP or
3α5βPOH (A), 3α5βPS or
3α5αPS (B), or β-estradiol or 10
μM picrotoxinin (PTXnin) (C). The top traces show currents
(I), and the bottom traces show the concomitant changes
in fluorescence (F). The modulators are sorted according to
their proposed classification into groups. All drugs inhibit the
electrophysiological response. The application of
3α5βPOH enhances whereas the application of
3α5βPS, 3α5αPS,
β-estradiol or PTXnin reduce the change in fluorescence (shown
with dotted lines). D, the summary of effects on electrophysiology and
fluorescence responses. ∗, p <
0.05; ∗∗, p < 0.01;
∗∗∗, p <
0.001.