Figure 3.
The effect of NT on firing rate is mediated by the NTS1 receptor. A, SR48692 (1 μm), an NTS1 receptor antagonist, blocked the effect of NT (100 nm) on the firing rate of DAergic neurons (black circles). The response of the control group (CTRL) (from Fig. 1C) is shown for comparison (gray circles). Basal firing rate in the presence of SR48692 was, on average, 0.6 ± 0.1 Hz. B, The elevation in [Ca2+]i induced by NT was also blocked by SR48692 and by SR142948A, a broader-spectrum NT receptor antagonist. The number of neurons responding to NT as a function of the total number of neurons tested is indicated below each column (Responsive neurons).