HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 569/3/939    most recent jphysiol.2005.099531v1 Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Huang, L. Articles by Li, L. Search for Related Content PubMed PubMed Citation Articles by Huang, L. Articles by Li, L.

¹ Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA

The vertebrate retina receives centrifugal input from the brain. In zebrafish, the major centrifugal input originates in the terminal nerve (TN). TN cell bodies are located in the olfactory bulb and ventral telencephalon. The TN projects axons to the retina where they branch in the inner plexiform layer (IPL) and synapse onto several inner retinal cell types, including dopaminergic interplexiform cells (DA-IPCs). This olfactoretinal centrifugal input plays a role in modulating retinal ganglion cell (RGC) activity, probably via dopamine-mediated Ca²⁺ signalling pathways. Normally, dopamine inhibits RGC firing by decreasing the inward Ca²⁺ current. Olfactory stimulation with amino acids decreases dopamine release in the retina, thereby reducing dopaminergic inhibition of RGCs. This model of olfacto-visual integration was directly tested by recording single-unit RGC activity in response to olfactory stimulation in the presence or absence of dopamine receptor blockers. Stimulation of the olfactory neurones increased RGC activity. However, this effect diminished when the dopamine D1 receptors were pharmacologically blocked. In isolated RGCs, the application of dopamine or a dopamine D1 receptor agonist decreased voltage-activated Ca²⁺ current and lowered Ca²⁺ influx. Together, the data suggest that olfactory input has a modulatory effect on RGC firing, and that this effect is mediated by dopamine D1 receptor-coupled Ca²⁺ signalling pathways.

(Received 29 September 2005; accepted after revision 19 October 2005; first published online 20 October 2005)
Corresponding author L. Li: Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA. Email: li.78{at}nd.edu

This article has been cited by other articles:

				A. Mousley, G. Polese, N. J. Marks, and H. L. Eisthen Terminal nerve-derived neuropeptide y modulates physiological responses in the olfactory epithelium of hungry axolotls (Ambystoma mexicanum). J. Neurosci., July 19, 2006; 26(29): 7707 - 7717. [Abstract] [Full Text] [PDF]