Fig. 10

Capsaicin and high K⁺ evoked calcium influx in primary DRG neurons of ELP mice. ChR2-flfl and Avil-ChR2 mice were exposed to blue light in a chamber on postnatal day P1-P5 together with the Cre-negative blue-insensitive mother. DRGs were obtained for calcium imaging experiments of n = 4 female mice per genotype at 50 weeks of age after finishing behavioral studies. A Time course of the calcium influx at baseline (0–200 s) and on stimulation with 0.1 µM capsaicin (100–200 s) to stimulate TRPVs positive DRG neurons and subsequently with high K⁺ (50 mM KCl) for 45 s (780–825 s) to evoke depolarization-evoked calcium influx. Data are presented as changes in fluorescence ratios (F340/380) normalized to baseline ratios and show means ± 95% confidence intervals CI, n = 150 neurons per genotype. B Violin plots of the capsaicin peak ratios and the ‘time to peak’. The peak fold increase was obtained by integration and was the first peak of at least 5 consecutive ratios greater than 10% above baseline. The line shows the median, the dotted lines show the interquartile range. The violin shows the distribution, obtained by Kernel density estimation. C In analogy to B, violin plots show the peak fold increase of [Ca²⁺]_i upon stimulation with high K⁺ perfusion. This was defined as the peak and time to peak > 780 s with greater than 20% raise above baseline of a minimum of 5 consecutive data points. The peak increase [Ca.²⁺]_i and the time to peak were compared with 2-sided, unpaired t-tests. Time courses were compared by 2-way ANOVA. Asterisks indicate statistically significant differences, ***P < 0.001; ****P < 0.0001