DISTRIBUTION OF GALANIN IMMUNOREACTIVE FIBERS IN THE MOUSE VOMERONASAL ORGAN

Galanin (GAL)-immunohistochemical techniques were applied to the mouse vomeronasal organ. GAL-immunoreactive fibers were seen in the recepto r-free epithelial region, but no fibers were found in the neuroepithel ial region. Many GAL-immunoreactive fibers were distributed around the cavernous blood vessels and the vomeronasal glands, and these fibers had a large number of varicosities and branches. GAL-immunoreactive fi bers were also distributed in both the olfactory epithelial area and t he respiratory epithelial area. GAL-immunoreactive cell bodies were se en in the trigeminal ganglion, in the sphenopalatine ganglion, and in the superior cervical ganglion. We concluded that, in the vomeronasal organ and the nasal mucosa, GAL functioned as a neuromodulator in the trigeminal sensory systems and in the vasomotor fibers of the autonomi c nervous systems.