Gonadotropin-releasing hormone agonist binding in tiger salamander nasal cavity

Binding of the iodinated gonadotropin-releasing hormone (GnRH) agonist, buserelin, was examined in the nasal cavities of tiger salamanders using in vitro autoradiography. Binding of [125I]buserelin was seen within the chemosensory epithelium of the main nasal cavity and Jacobson's (vomeronasal) organ. Highest levels of binding were observed over the chemosensory neuron dendrites. Given the apparent lack of GnRH-immunoreactive fibers within the chemosensory epithelium as we have observed in a previous study, these observations suggest that GnRH may diffuse from fibers in the lamina propria of the chemosensory mucosa into the sensory epithelium to modulate chemosensory reception.