Figure 3.

The onset time course of presynaptic inhibition mediated by PTX-insensitive and PTX/RGS-insensitive Gα subunits. Superimposed plots of normalized presynaptic inhibition vs. time, with drug application at 0 s. Each point represents the mean ± SEM, with the number of experiments (n) given in parentheses in the legend. Presynaptic inhibition was normalized by using data points 6 s before and at least 20 s after drug application (20 μM adenosine, 50 μM baclofen). In all experiments where Gα subunits were expressed, neurons were pretreated with PTX.