Figure 5
From: Presynaptic action of neurotensin on dopamine release through inhibition of D2 receptor function
NT enhances train-pulse evoked DA overflow through inhibition of D 2 autoreceptor function. A) Sulpiride (5 μM) alone was first pre-applied. With sulpiride present in the bath, NT (8–13) (100 nM) was introduced for a total of 8 min. The graphs represent the average amplitude and kinetics of train pulse-evoked DA overflow recorded during the control period (left), in the presence of sulpiride alone (middle) and in the presence of both NT (8–13) + sulpiride (right) (n = 10). Sulpiride alone enhanced peak DA overflow by 81% compared to control. In the presence of sulpiride, NT (8–13) only caused a small additional increase in DA levels (by 13% compared to the sulpiride alone condition) (n = 10). B) Summary graph showing the time course of the effect of NT (8–13) on peak DA overflow evoked by train-pulse stimulation following D2 receptor blockade by sulpiride (n = 10).