Fig. 3
Stimulation of the efferent, but not afferent, vagus or of the splanchnic nerve elicits a NE voltammetry signal in the spleen. a Representative time-resolved voltammograms elicited by electrical left vagus nerve stimulation (VNS) (10–70 µA intensity, 500 µs pulse width, 10 Hz frequency, 10 s duration) or sham stimulation. Top and bottom panels are similar to those in Fig. 1c. The dashed vertical line denotes onset of VNS. b NE oxidation charge (Qo) in response to different VNS intensities in 3 animals; lines represent least square fits on data from each animal and r2 the respective coefficients of determination. c Time course of NE oxidation current (io) elicited by VNS (top panel), associated heart rate and breathing rate responses (2 middle panels); Qo values are shown in bottom panel, in 3 animals before and after distal vagotomy. d Same as c, but for proximal vagotomy. e Representative NE oxidation current trace elicited by optogenetic VNS in ChAT–ChR or in Vglut2–ChR mice (top panel), along with the associated heart rate and breathing rate responses (2 middle panels); Qo values from 3 animals in each case are shown in bottom panel. f Representative time-resolved voltammograms elicited by electrical left splanchnic nerve stimulation (500 µA intensity, 100 µs pulse width, 2, 4, and 30 Hz frequency, 10 s duration). Top and bottom panels are similar to those in Fig. 1c. g Qo values during splanchnic nerve stimulation using 2 (n = 8), 4 (n = 8), and 30 Hz (n = 6) pulsing frequency. p by ANOVA with multiple comparisons