Fig. 2: The activities of l/vlPAG SST⁺ neurons highly correlate with urination.

a Schematic of AAV-DIO-GCaMP6f injection (left) and optical fiber implantation (middle) in SST-Cre mice. Representative image of GCaMP6f-labeled SST⁺ neurons in the l/vlPAG (right). b Schematic of fiber photometry for Ca²⁺ signal detection and real-time urination tracking. c Example Ca²⁺ fluorescent signal trace in experimental mice expressing GCaMP6f in l/vlPAG SST⁺ neurons during urination event (left). Averaged Ca²⁺ signals (middle) and heatmaps of individual traces (right) from experimental mice expressing GCaMP6f (n = 86 trials from 8 mice) aligned to each urination event. Black arrows and dotted bars indicate urination onsets. d Example fiber photometry trace from control mice expressing GFP in l/vlPAG SST⁺ neurons during urination (left). Averaged fiber photometry traces (middle) and heatmaps of individual traces (right) from control mice expressing GFP (n = 82 trials from 7 mice) aligned to each urination event. e Quantification of peak amplitudes of Ca²⁺ signals from all fiber photometry traces across experimental mice expressing GCaMP6f (n = 8 mice) and control mice expressing GFP (n = 7 mice). **P = 0.001 (Wilcoxon rank-sum test). f Quantification of the percentage of Ca²⁺ signals that correlated with each urination. ***P < 0.001 (GCaMP6f group versus GFP group, Wilcoxon rank-sum test). g Onset of each urination-associated Ca²⁺ signal from experimental mice expressing GCaMP6f plotted to the onset of urination event at time = 0 s. h Averaged Ca²⁺ signals (red) from experimental mice expressing GCaMP6f aligned to the onset of each urination event or to shuffled urination events (black). All data are presented as mean ± SEM.