Extended Data Fig. 8: MTCs sustain their food odour-induced neuronal activation up to 3 hours.
From: A food-sensitive olfactory circuit drives anticipatory satiety
a) Left: Food odour stimulation paradigm. Top: odour valve commands, Bottom: food odour concentration. Right: Higher magnification of first (i) and last (ii) odour pulse average ± SEM [n = 3 trials]. b) Top: Distribution of latency times between valve command and odour detected by photoionisation detector (PID) [n = 480 presentations]. Bottom: Distribution of PID signal rise time [n = 480 presentations]. c) PID signal amplitude as a function of odour stimulus duration [n = 10-130 presentations]. d) GCaMP6f recording in awake mice and representative images of plane 1 (i) and 5 (ii) (an example neuron indicated in red). Scale bars: 50 µm. e) Average calcium activity traces of region of interest (ROIs) in response to food odour stimuli of varying duration shown ± SEM [10-130 trials per stimulus]. Neurons 1 and 2 correspond to ROIs indicated in (d). f) Average responses of all identified neurons [n = 408 ROIs from 2 animals, n = 110 stimulations, 1 s duration]. Timepoint 0 indicates the onset of odour presentation. g) Activity profiles of all neurons in response to food odours, separated into excitatory and inhibitory responses. h) GCaMP6f fluorescence from 6 stacked planes gained from volumetric imaging (total volume scanned=180 µm, z-distance=30 µm, maximum projections of 3200 frames). i) Top: Calcium activity time series of an example ROI over the duration of the whole experiment with valve commands shown in green. Right: Segments of the time series at extended timescales at early (i) and late (ii) time points in the experiment. Bottom: Integrals of calcium activity in response to each 2 s-long trial of food odour stimulation [n = 110] fitted with linear regression shown in red (slope=0.005). j) GCaMP6f recording in anaesthetized mice and representative images of planes 3 (i) and 4 (ii) (example neuron indicated in red). Scale bars: 50 µm. k) Example activity of neurons in response to food odours. Depicted is the mean of 30-180 trials ± SEM. Neurons 1 and 2 correspond to ROIs indicated in (j). l) Averaged responses of all identified neurons [n = 401 ROIs from 2 animals, n = 180 stimulations]. Timepoint 0 indicates the onset of odour presentation. m) Activity profiles of all neurons in response to food odours, separated into excitatory and inhibitory responses. n) GCaMP6f fluorescence from 6 stacked planes gained from volumetric imaging in an anaesthetized animal (total volume scanned=150 µm, z-distance=25 µm, maximum projections of 3200 frames). o) Top: Calcium activity time series of an example neuron over the entire duration of the experiment with individual odour stimulations indicated by black dots. Food odour exposure segments of the trace are depicted in green. Below: Integrals of calcium activity in response to food odours fitted with linear regression [n = 180 stimulations]. Below: Segments of the time series at extended timescales at early (i), middle (ii) and late (iii) time points. Mouse images in d and j adapted from SciDraw under a Creative Commons license CC BY 4.0.
