Figure 2.
5-HT2A/2CR and 5-HT7R are largely responsible for the inward current produced by 5-HT. A, Under voltage-clamp, representative traces of slow inward currents elicited by bath application of 10 μm or iontophoresis of 50 mm 5-HT were almost completely abolished by 10 μm ketanserin (A1, A2), partially blocked by 2 μm MDL-11939 (A3), or 1 μm SB-269970 (A4). Iontophoresis of 5-HT indicated by arrowhead. In this figure and following figures, gray dashed lines denote basal holding currents or the resting membrane potential before application of 5-HT. B, Summary of currents evoked by 5-HT (1 μm, n = 7; 5 μm, n = 7; 10 μm, n = 35), and α-methyl-5-HT (25 μm, n = 4). C, Summary of effects of ketanserin (n = 9), MDL-11939 (n = 11), SB-242084 (n = 6), SB-269970 (n = 6), and coapplication of SB-269970 plus MDL-11939 (n = 4) on the 5-HT-induced current. Error bars are ± SEM.