Fig. 2.

LTH is not attributable to continuing stimulation by Ppr and can be induced by direct stimulation of adenylyl cyclase. A, 10-s representative traces of neurons recorded when clamped at −45 mV after prior 6-h treatment with either vehicle (“Veh”, 0.01 % DMSO), Ppr (1 µM) alone, Ppr followed by overnight treatment with either 5-HT4 receptor blocker GR113808 (1 µM) or GR113808 alone (“GR”). B, proportions of neurons with OA at −45 mV in each experimental condition. C, 10-s representative traces of neurons recorded at −45 mV after prior 6-h treatment with vehicle (0.01 % DMSO) or adenylyl cyclase activator forskolin (1 µM). D, proportions of neurons with OA at −45 mV. For B and D, the number of neurons exhibiting OA over the total number sampled is reported above each bar. Comparisons performed against the vehicle condition with Fisher’s exact test. In B, p < 0.017 was considered significant after Bonferroni correction for 3 comparisons while in D, p < 0.05 was considered significant for a single comparison. Fsk, forskolin; MP, membrane potential; NS, non-significant; OA, ongoing activity; Ppr, prucalopride; Veh, vehicle.