Electrophysiology of the Terminal Nerve in Cyprinid Fish
The terminal nerve(nervus terminalis) is found in various species of vertebrate classes including man. In selachians, the terminal nerve is an independent bundle distinct from the olfactory nerve and tracts, while in other vertebrates, the ganglion cells of the terminal nerve(TN cells) and their processes are distributed within or along the olfactory pathway. Recent studies in teleosts have revealed several new features of the terminal nerve. The terminal nerve projects to some telencephalic areas, that seem to be involved in sexual behavior, as well as to the retina. It contains neuropeptides related to luteinizing hormone-releasing hormone and to molluscan cardioexcitatory peptide. Lesion and stimulation studies have suggested that the terminal nerve trasmits sexually relevant chemosensory information.
Despite the biological significance stated above, the physiological properties of the terminal nerve are largely unknown. In the present paper, I demonstrate the characteristic intracellular responses of TN cells to electrical stimulation of the olfactory nerve(ON) and tracts.