Extended Data Fig. 3: Layer V projection neurons are silenced in a model of c-MS.
a, Schematic of the experimental timeline to study longitudinal activity in apical dendrites of layer V projection neurons in the cortical MS model (c-MS) by in vivo imaging of Thy1-GCaMP6f x BiozziABH mice. b, In vivo multiphoton image of layer V apical dendrites over the course of c-MS through a cranial window; left, before cytokine injection (baseline MOG) and right 3 days (c-MS d3) post cytokine injection. Top: Merged GCaMP6f and autofluorescence channels allow the identification of apical dendrites (green only). Middle: GCaMP6f channel masked and color-coded for cytoplasmic Ca2+ events per minute. Bottom: Representative calcium activity traces displayed as delta f/f for the four apical dendrites marked in the middle panel. c, Cumulative plots representing activity for the entire population of apical dendrites for each selected time point over the course of the c-MS model. Insets: Mean activity normalized to baseline for MOG shown as mean + SEM (n = 3 c-MS mice, two-tailed paired t-test, P = 0.035). d, Heat map representation of ranked activities for single dendrites between baseline MOG and c-MS d3. e, Spine density of dendritic stretches of pyramidal layer V neurons from c-MS d3 mice used in b-d (imaged area was used for quantification) and control mice (n = 30 and n = 40 dendritic stretches from 3 and 4 mice respectively; mean + SEM, two-tailed unpaired t-test, P = 0.0038). Scale bar in b, 20 µm. See Source Data file for individual data points and further statistical parameters. **P < 0.01, *P < 0.05.
