Fig. 4.

Effects of endothelin-1 (ET-1) and angiotensin II (ANG II) on the nucleoplasmic and PM Ca²⁺ increase in rat PASMCs. A: 2D confocal images of PASMCs cotransfected with Lyn-D3cpv and 3NLS-D3cpv, showing cpV fluorescence (a), and Ca²⁺ mobilization in the PM and nucleoplasm before (b) and after (c) ET-1 (30 nM) treatment. B: ΔFRET fluorescence ratio traces showing Ca²⁺ mobilization in the PM (ROI 1 and 3) and nucleoplasm (ROI 2 and 4) of rat PASMCs (from A) after ET-1 treatment. C: statistical analysis of the peak normalized ΔFRET fluorescence ratio of ET-1-induced Ca²⁺ transients in the nucleoplasm and PM of rat PASMCs. One-way ANOVA was used to calculate P values. **P < 0.001; n = 8. Error bars denote SE. D: 2D confocal images of the cells cotransfected with Lyn-D3cpv and 3NLS-D3cpv, showing cpV fluorescence (a), and Ca²⁺ mobilization in the PM and nucleoplasm before (b) and after (c) ANG II (100 nM) treatment. E: ΔFRET fluorescence ratio traces showing Ca²⁺ mobilization in the PM (ROI 1 and 3) and nucleoplasm (ROI 2 and 4) of rat PASMCs (from D) after ANG II treatment. F: statistical analysis of the peak normalized ΔFRET fluorescence ratio of ANG II-induced Ca²⁺ transients in the nucleoplasm and PM of rat PASMCs. One-way ANOVA was used to calculate P values. **P < 0.001; n = 12. Error bars denote SE. G and H: time course showing changes in nucleoplasmic and PM [Ca²⁺] in a single cell upon treatment with ET-1 and ANG II.