Electroacupuncture ameliorates visceral hypersensitivity and negative emotions by regulating paraventricular hypothalamic nucleus and colonic corticotropin-releasing factor signaling

Figure 3 Corticotropin-releasing factor-ergic neurons of the paraventricular hypothalamic nucleus participate in the effect of electroacupuncture. A: Immunofluorescence plots of the paraventricular hypothalamic nucleus (PVN) in the control group, model group and model + electroacupuncture (EA) (Baihui + Tianshu + Dachangshu) group [c-fos is red, Corticotropin-releasing factor (CRF) is green, and 4,6-diamidino-2-phenylindole is blue]. Scale bar, 124.5 μm; B: Statistical plot of the c-fos and CRF co-labelling rates in the PVN. Each group n = 6, model group vs control group, model + EA group vs model group, ^bP < 0.01; C: The virus (red fluorescence) was expressed in the PVN. Scale bar, 249 μm; D: Injection of the chemogenetically activated virus rAAV-CRH-hM3D(Gq)-mCherry-WPREs into bilateral PVNs and intraperitoneal injection of saline, clozapine-N-oxide (CNO), or CNO plus EA after 21 days; E: Statistical graphs of the amount of saline injected into the mice in the colorectal dilatation assay; F: Paths travelled by mice in each group in the open-field test; G: Statistical graphs of distance in center and time in center by mice in the open-field test; n = 6 mice in each group, hM3Dq + CNO group vs hM3Dq + saline group, hM3Dq + CNO + EA group vs hM3Dq + CNO group; ^aP < 0.05, ^bP < 0.01; CRF: Corticotropin-releasing factor; PVN: Paraventricular hypothalamic nucleus; EA: Electroacupuncture; CNO: Clozapine-N-oxide; DAPI: 4,6-diamidino-2-phenylindole.