Figure 4.
AngII potentiates L-type Ca2+ currents in second-order sensory NTS neurons. A, Representative traces of the whole-cell Ca2+ current in control conditions, with AngII (2 μm), or after wash with the control buffer. The dashed line indicates zero level of the current. HP = -60 mV; SP = -20 mV. B, Percentage of changes in amplitudes of the L-type and transient Ca2+ currents in control (Ctrl) conditions, with AngII (2 μm) (n = 8), or after wash with the control buffer (n = 4). C, The concentration-response curve of the AngII-mediated effect on L-type Ca2+ currents. The EC50 was 37.4 nm, and the Hill slope coefficient was 1.45. The dashed line is the fitted curve. D, The I-V curve of L-type Ca2+ currents in control (♦) conditions shows that this current is high-voltage threshold activated (n = 4). In the presence of AngII (100 nm) (□), the amplitude of the L-type Ca2+ current increased only at a range of negative stepping potentials, especially at -10 and -20 mV (n = 4). *p < 0.05.