Figure 7.

The pharyngeal nervous system can excite feeding during SIQ, but not during DTQ. A, 10 mm 5-HT stimulates feeding during SIQ, but not during DTQ. n = 8–10. B, Optogenetic excitation of all cholinergic pharyngeal neurons (AChN) by wide-field fluorescence stimulates feeding in worms on bacterially seeded agar plates during SIQ, but not during DTQ. n = 13 for each group. C, Optogenetic excitation of pharyngeal muscle stimulates feeding in the presence of 10 mm 5-HT during wake, but not during DTQ. n = 10. D, Ca²⁺ transients are absent from pharyngeal muscle during DTQ and cannot be stimulated by muscle excitation. The difference between maximum and minimum GCaMP6s intensity of a region of the metacorpus of the pharynx during an ∼30 s interval was calculated for each condition to measure the magnitude of Ca²⁺ transients. n = 10. E, GCaMP6s fluorescence from a region of the metacorpus from one representative worm during wake. F, GCaMP6s fluorescence from a region of the metacorpus from one representative worm during DTQ. a.u., Arbitrary units in D–F. Statistical significance was calculated using Student's t test. *p < 0.05, **p < 0.01, ***p < 0.001.