Figure 3.
Mn2+ quenched the fura-2-dextran fluorescence intensity. Repetitive [Ca2+]cy spikes (bottom) and repetitive transient hyperpolarizations of the plasma membrane (E/mV, top) were induced by 1 mm SrCl2 in the external medium. The additional perfusion of 0.1 mm MnCl2 (bars on top) decreased the fluorescence intensity emitted by fura-2-dextran (middle traces, given in arbitrary units, a.u.) at both excitation wavelengths, 340 nm (shifted upward by 25 a.u. for clarity) and 380 nm. Sampling frequency was 1/6 s−1.