Fig. 5.

Time-dependent changes in intracellular Ca²⁺. Human cardiac fibroblasts were stimulated, in a fluorescence-based assay for detecting changes in intracellular Ca²⁺ over time, with the following: A) glutamate (10⁻⁴ M), B) 5-HT (10⁻⁵ M) or C) ATP (10⁻⁴ M). AUC and peak values of Ca²⁺ transients are shown. The cells were obtained from 4 experiments. A) Ca²⁺ responses to glutamate and B) 5-HT in cardiac fibroblasts, when stimulated with LPS (10 ng/ml) for 24 h; unstimulated cells were used as controls. Results from a typical experiment are shown and the AUC, reflecting the amount of Ca²⁺ released, was analyzed to measure strength of each Ca²⁺ response. The amplitude is expressed as the maximum peak value. For statistical analysis, a paired Student’s t-test was used to compare unstimulated and LPS stimulated cells (n = 4), *P < 0.05, **P < 0.01.