Figure 1
5-HT7 receptor activation increases NMDA-evoked currents in isolated hippocampal neurons. A) 50 nM 5-CT was applied to isolated CA1 hippocampal neurons for 5 min beginning at min 5 after a stable baseline of NMDA-evoked currents was established (closed circles). For the control data, vehicle (ECF) was continuously applied for 30 min. In samples treated with the 5-HT7 receptor antagonist, SB 269970 (1 μM) was included in the bath and was present before, during, and after 5-CT application. NMDA-evoked currents were recorded every 60 s by application of 50 μM NMDA, 0.5 μM glycine for 3 s. Recordings continued for at least 20 min after drug application. Peak currents were averaged for 5 min prior to applying 5-CT and were compared with currents averaged for values between 26 and 30 min. Data are representative of 5–6 independent experiments for each condition. B) Sample traces from the same cell treated with 50 nM 5-CT are shown at minute 3 (black trace) or minute 28 (gray trace). C) 5-HT7 antagonist SB269970 prevents the enhancement of INMDA by 5-CT. ** Indicates p < 0.01, one-way ANOVA (Turkey’s post hoc comparison).