Olfactory input increases visual sensitivity in zebrafish: a possible function for the terminal nerve and dopaminergic interplexiform cells
- Maaswinkel, H. and Li, L.
- The Journal of experimental biology 206(13): 2201-2209 (Journal)
- Registered Authors
- Li, Lei, Liu, Ningai, Maaswinkel, Hans
- MeSH Terms
- Amino Acids/pharmacology
- Olfactory Pathways/physiology*
- Photic Stimulation
- Stimulation, Chemical
- Visual Perception/drug effects*
- Visual Perception/physiology*
- 12771169 Full text @ J. Exp. Biol.
Maaswinkel, H. and Li, L. (2003) Olfactory input increases visual sensitivity in zebrafish: a possible function for the terminal nerve and dopaminergic interplexiform cells. The Journal of experimental biology. 206(13):2201-2209.
Centrifugal innervation of the neural retina has been documented in many species. In zebrafish Danio rerio, the only so-far described centrifugal pathway originates from terminal nerve (TN) cell bodies that are located in the olfactory bulb. Most of the TN axons terminate in the forebrain and midbrain, but some project via the optic nerve to the neural retina, where they synapse onto dopaminergic interplexiform cells (DA-IPCs). While the anatomical pathway between the olfactory and visual organs has been described, it is unknown if and how olfactory signals influence visual system functions. We demonstrate here that olfactory input is involved in the modulation of visual sensitivity in zebrafish. As determined by a behavioral assay and by electroretinographic (ERG) recording, zebrafish visual sensitivity was increased upon presentation of amino acids as olfactory stimuli. This effect, however, was observed only in the early morning hours when zebrafish are least sensitive to light. The effect of olfactory input on vision was eliminated after lesion of the olfactory bulbs or after the destruction of DA-IPCs. Intraocular injections of a dopamine D(2) but not a D(1) receptor antagonist blocked the effect of olfactory input on visual sensitivity. Although we cannot exclude the involvement of other anatomical pathways, our data suggest that the TN and DA-IPCs are the prime candidates for olfactory modulation of visual sensitivity.
Genes / Markers
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Engineered Foreign Genes