Validation of Sst-Cre line and Sst antibody labeling of pre-BötC glutamatergic and Dbx1-derived neurons. A, Confocal fluorescence microscopy images at low magnification showing Sst antibody-labeled neurons within the pre-BötC in a representative fixed coronal section from adult VgluT2-tdTomato mouse. VS, Ventral surface; d, dorsal; m, medial. B, C, Confocal fluorescence microscopy images of a pre-BötC subregion at higher magnification showing VgluT2 Cre-dependent tdTomato neuronal labeling (red; B), Dbx1 Cre-dependent tdTomato labeling (red; C), and immunolabeling with Sst antibody (green) in pre-BötC neurons. Arrows in the merged image in B and C indicate the coexpression of Sst in tdTomato-labeled VgluT2-expressing and Dbx1-derived neurons. D, Confocal images of a pre-BötC subregion in a fixed section from the Sst-tdTomato double-Tg mouse strain illustrating tdTomato neuronal labeling (red) and immunolabeling with Sst antibody (green) colocalized with tdTomato (arrows and merged image). All images have the same dorsomedial anatomical orientation.