Figure 5.

Neurons in MVN activated by sGVS, visualized in vibratome sections processed for c-Fos immunoperoxidase/diaminobenzidine staining. The panels illustrate six rostro-caudal levels of the MVN from the same sGVS-stimulated rat. The images were obtained using the same microscopy and imaging conditions, and were subject to the same adjustments of brightness and contrast (see Materials and Methods). In all panels, the midline is to the left. A dense cluster of immunopositive cells is present in the rostral pole of MVNpc (A,B). The few activated neurons in MVNmc (A–D) are small diameter cells; none of the larger diameter neurons of this region were c-Fos-positive. c-Fos-stained cells were scattered throughout the caudal spinal vestibular nucleus (B–F). Approximate Bregma levels are indicated in the upper right of each panel. Abbreviations: MVN, medial vestibular nucleus; MVNmc, medial vestibular nucleus, magnocellular division; MVNpc, medial vestibular nucleus, parvocellular division; NTS, nucleus tractus solitarius; SpVN, spinal vestibular nucleus. Scale bar in (F) represents 100 μm, and is for all panels.