Comparison of norepinephrine (NE) dynamics in naïve Lewis (L) and Sprague-Dawley (SD) rats. (a) Representative concentration traces demonstrating NE release and uptake in the ventral bed nucleus of the stria terminalis (vBNST) of both SD and L rats (scale bar, 100 nM; gray box =stimulation, 60 pulses, 60 Hz). (b) Input–output curve of [NE]max at 20, 40, 60, 80, 100 and 120 pulses in SD and L rats. (c) Histogram of mean clearance half-life of NE following 60 Hz, 60 pulse stimulation in both SD and L rats.