Fig. 2. Relative cytosolic fluorescence intensities of the Ca²⁺ indicators (mean and s.d.; control=fluorescence intensity before the application of the peptide=100%) at the maximal values of the time-dependent response (Fig. 6) in HaCaT keratinocytes (A,B) and human melanocytes (C,D) after stimulation with different concentrations of URC (A,C) and using different extracellular medium and preincubation conditions (B,D). *Statistically significant differences (P<0.05, unpaired t-test) from the control; +, statistically significant differences (P<0.05, unpaired t-test) from the effect after stimulation with 10^-10 M URC. Number of cells recorded (n) is shown in the respective columns.