Fig. 6
From: Optogenetic activation of serotonergic neurons changes masticatory movement in freely moving mice
Optogenetic activation of ROb 5-HT neurons during voluntary mastication does not affect masticatory movement patterns. (a) Schematic illustration of the position of the optical fiber stereotaxically inserted into the ROb of double transgenic mice expressing ChR2 in central 5-HT neurons. (b) Representative EMG recordings of digastric and masseter muscles during the resting state before and after optogenetic activation of ROb 5-HT neurons by blue light application (blue bar). (c) Pooled data for the percentage of EMG activity evoked after yellow (control) or blue light (activation) illumination to that during the resting state before illumination in the digastric and masseter muscles. (d) Representative EMG recordings of digastric and masseter muscles during voluntary mastication before and after blue light application (blue bar) for optogenetic activation of ROb 5-HT neurons (left). Expanding EMG recordings in dotted box outlines of left EMG recordings (right). (e) Pooled data for masticatory frequency after yellow or blue light application. (f) and (g) Pooled data for RMS peak amplitude (f) and duration (g) in masseter EMG bursts after yellow or blue light application. (h) and (i) Pooled data for RMS peak amplitude (h) and duration (i) in digastric EMG bursts after yellow or blue light application. *P < 0.05 (paired Student’s t-test). Comparisons with n.s. have P > 0.05 and are considered not significant. Data are expressed as mean ± SEM. ROb raphe obscurus nucleus.
