Fig. 2.
AngII- and KCl-induced changes in [Ca2+]i are mediated by AT1R or LTCC, respectively. A–C AT1R inhibitor losartan significantly reduces the AngII-induced calcium transient in HL-1 cells. Cells were superfused either with 100 nM AngII (control) or with AngII plus 10 µM losartan. A Calcium transient peak of all cells (responding and non-responding cells combined) is reduced in losartan-treated cells. B Losartan also leads to diminished calcium transients in responding cells. C The proportion of non-responding cells is increased by losartan. Control: N = 2, n = 42–66 cells, losartan: N = 2, n = 24–39 cells (single data points). D, E LTCC blocker verapamil significantly reduces intracellular calcium increase in response to 25 mM KCl in HL-1 cells. Cells were superfused either with KCl (control) or with KCl plus verapamil. The baseline shift upon KCl superfusion is significantly reduced in verapamil-treated cells (D). F The dramatically reduced response when analysing all cells in this setting is in part due to an increase of non-responding cells. Concentration of verapamil: 20 µM, straight line indicates median, dotted line indicates mean, *p < 0.05, N = 4 (single data points), n = 54–78 cells each