FIGURE 1.

TLQP-21 stimulation of intracellular Ca²⁺ levels in CHO cells. (A) Cells were loaded with FLUO-4 NW and fluorescence emissions were measured at 485/535 nm (excitation/emission filters) every 0.5 s for the 60 s following injection of the stimuli. TLQP-21 was applied at concentrations ranging from 1 nM to 10 μM. Ca²⁺ mobilizing activity of TLQP-21 is plotted in terms of maximal response obtained at each given concentration in CHO cells. To ascertain the specificity of the effects, cells were also challenged with 1 nM–10 μM LRPS-21, a scrambled peptide containing the same amino acid residues of TLQP-21. (B) Effects of repeated stimulation with TLQP-21 on intracellular Ca²⁺ levels in CHO cells. 10 μM TLQP-21 was applied three times at 5 min intervals. Fluorescence was recorded every 0.5 s. Results are the means ± SEM of measurements obtained in at least six different wells for each experiment. All experiments have been repeated at least three times.