Localization of somatostatin-like immunoreactive neurons in the vestibular ganglion of the rabbit.

The presence of somatostatin-like immunoreactive neurons was examined in the rabbit vestibular ganglion by using immunohistochemical techniques. About 22% (n = 153) of the total ganglion cells (n = 699) examined were somatostatin-immunoreactive and they were diffusely present throughout the ganglion. Majority of the somatostatin-immunoreactive cells were large (long diameter, 23-31 microns, 74%; short diameter, 20-25 microns, 76%) and they had oval or spherical cell bodies with well developed Nissl's body. However, about 78% (n = 546) of the total ganglion cells examined were not immunoreactive to the somatostatin. The presence of the somatostatin-immunoreactive neurons in the vestibular ganglion suggests a possibility that somatostatin may be involved in the modulation of afferent sensory transmission from the vestibular organ of the rabbit.