Figure 2.

Naloxone-precipitated withdrawal produces norepinephrine overflow in the ventral bed nucleus of the stria terminalis (vBNST). (a) Schematic of electrode placement and experimental timeline. (b, c) Representative norepinephrine (NE) response at baseline, after morphine or vehicle, and after naloxone. NE current is isolated from corresponding color plots using principal component analysis. Asterisk suggests oxidation of metabolite. (d) Total NE release events during morphine/vehicle and subsequent naloxone. ***P<0.001, two-way repeated measures ANOVA with Bonferroni post hoc. (e) Release amplitude during morphine/vehicle and subsequent naloxone. Bars are average ±SEM with individual events overlaid. (f) Representative evoked NE after treatment in morphine–naloxone and vehicle–naloxone animals and (g) data from all subjects. *P<0.05, Welch's corrected unpaired t-test. DS, dorsal striatum.