Extended Data Fig. 1: Characterization and validation of ketamine-induced adenosine signals.
From: Adenosine signalling drives antidepressant actions of ketamine and ECT
a, Schematic of fiber photometry setup for monitoring GRABAdo1.0 signals. b, Schematic diagram of acute hypoxia chamber (left) and real-time fluorescence changes of GRABAdo1.0 and GRABAdo1.0-mut probes in the mPFC during acute hypoxia (right; red line). Blue dashed line represents oxygen levels. c, Adenosine signals were not detected in the nucleus accumbens (NAc) following ketamine administration (10 mg·kg−1, i.p.) compared to saline control. Scale bar, 1 mm. d-h, Quantification of GRABAdo1.0 signals induced by ketamine (10 mg·kg−1, i.p.) in the mPFC, ACC, and HPC, showing adenosine peak amplitude (d), average time to peak (e), onset time (f), rise time (g), and decay time (h). i, Two-photon images show fluorescence changes of the GRABAdo1.0 probe in the prefrontal cortex at 0 s (top) and 200 s (middle) following ketamine and saline administration. Bottom, corresponding time-course heatmaps for each region of interest (ROI). Scale bar, 50 µm. j, Heatmaps showing extracellular adenosine changes in the cortex at different time points after ketamine and saline administration. Scale bar, 50 µm. k, Time course of mean adenosine levels in prefrontal cortex ROIs following ketamine or saline administration. l, Area under the curve (AUC) of adenosine levels in the mPFC of CRS and naive mice after ketamine administration (10 mg·kg−1, i.p.), normalized to the naive group. m, n, Rise time (m) and decay time (n) of GRABAdo1.0 signals in the mPFC in response to different ketamine doses. o, p, Specificity of the GRABAdo1.0 probe validated in cultured HEK293T cells. o, Heatmaps and p, time course of fluorescence changes following application of adenosine and ketamine (n = 15 cells per group). Scale bar, 10 µm. Data are mean ± s.e.m. (shading in b, c, p; error bars in d-h, l-n). Statistical analyses used a two-tailed unpaired t-test (c, l) and one-way ANOVA (m, n) (***P < 0.001). See Supplementary Table 1 for detailed statistics. The schematics in a and b were created using BioRender (https://www.biorender.com).
