Fig. 2

The activation of GABA B-Rs in the GP increases the firing rate of RTn neurons. A Sample of raw traces of the basal (left) firing activity of RTn neurons and their firing activity after (right) microinjection of GABA B agonist baclofen into the GP. The voltage and time scales apply to both traces. B Peri-event histogram and raster representation of the spiking activity of RTn neurons after administration of 300 ng of baclofen into the GP. The black horizontal segment and dashed line represent the injection period. Both graphs are of the same neuron. C Statistical analysis the effect of the application of different concentrations of baclofen to the ipsilateral GP on the RTn neuron firing rate. The effect is expressed as percent changes from the basal activity. No significant difference was observed between all doses applied to the GP (p = 0.5511; one-way ANOVA). Ten neurons showed a decreased firing rate after baclofen treatment (p = 0.00034, paired t test), and seven neurons showed no response to any concentration (p = 0.056; paired t test). Each circle represents one neuron—NS: not significant; *** p < 0.05. D Heatmap of the normalized (z score for the mean) firing rate of all neurons recorded before and after baclofen application into the GP. All doses of baclofen tested are represented. The orange horizontal bar represents the injection period. E Statistical analysis of the effects of all doses of baclofen on the burst index compared with the basal (300 ng: p = 0.50, paired t test; n = 12 neurons. 100 ng: p = 0.20, paired t test; n = 12 neurons; 300 pg: p = 0.27, paired t test; n = 10 neurons.). Each symbol represents one neuron. F Representation in the coronal plane of the recording sites and type of response of RTn neurons. G The graph represents the type of response of RTn neurons as a percentage