FIGURE 8.

Immunofluorescence labeling for Phox2b. (a–i) Direct comparison of immunofluorescence labeling between guinea pig polyclonal [green, “Phox2b (GP)”; (Nagashimada et al., 2012)] and mouse monoclonal [red, “Phox2b (Ms)”; sc‐376997] anti‐Phox2b antisera, combined with TH immunofluorescence (magenta) to identify LC neurons. In addition to confirming antibody specificity, labeling Phox2b across three rostral‐to‐caudal levels of the PB region highlighted the extensive population of non‐LC (glutamatergic) Phox2b neurons, which form an observer‐independent ventromedial border for the PB. Approximate bregma levels are shown at bottom‐left in (a, d, g). Scale bars in (c, f, i) are 200 μm, and each scale bar applies to other panels in the same row