Extended Data Fig. 3: Microendoscopy reveals acclimation-induced VMPOLepR warm responsiveness in vivo.
From: Thermally induced neuronal plasticity in the hypothalamus mediates heat tolerance
a, Top: schematic of experimental configuration indicating AAV-mediated GCaMP6f delivery into VMPOLepR neurons and GRIN lens implantation. Bottom: experimental timeline. b, Representative images showing GCaMP6f expression in VMPOLepR neurons, and location of the GRIN lens implant. c, Left: maximal projection image from a representative imaging session and location of the regions of interest (ROI). Right: calcium dynamics from 6 representative neurons recorded from a non-acclimated mouse at RT (22 °C) and at 36 °C. Note that some cells increase (red traces), decrease (blue trace) and don’t change (grey trace) activity. d, Cumulative distribution plots of the activity (averaged z-scores) of all extracted neurons in 4 mice upon increasing ambient temperature acutely from RT (22 °C) to 36 °C, before and after acclimation for 30 days at 36 °C. Mann-Whitney U test, ***P < 0.0001 for cumulative fraction at 36 °C Pre vs Post acclimation. e, Cumulative distribution plots of the activity (averaged z-scores) of all extracted neurons in 2 time-matched control mice upon increasing ambient temperature acutely from RT to 36 °C, before and after sham acclimation. The time-matched controls did not undergo acclimation to temperature but stayed at at 22 °C for 30 days in between recording sessions. Mann-Whitney U test, P = 0.2273 (Sham #1) and P = 0.3624 (Sham #2) for cumulative fraction at 36 °C Pre vs Post sham acclimation. f, Representative calcium dynamics (ΔF/F) traces in 8 randomly selected cells from mouse #2 from panel d before (Pre-accl.) and after heat acclimation (Post-accl.). g, Representative VMPOLepR that could be reliably tracked and recorded before and after acclimation (30 days in between recording sessions) in 2 acclimated mice, and in a time-matched RT control mouse. Activity of single cells upon changes in ambient temperature from 22 °C to 36 °C. Cells were longitudinally recorded before (pre) and after (post) temperature acclimation. h, Summary plots of calcium transients in 2 mice (left, middle) before and after heat acclimation with the mouse kept at 22 °C during recordings and a non-acclimated mouse with matched inter-recording interval in between recording sessions (30 days) (right); related to panel h. Data based on N=4 acclimated animals and N=2 time-matched non-acclimated animals. Data shown as mean ± s.e.m.
