Institutional Research Information Service
UCL Logo
Please report any queries concerning the funding data grouped in the sections named "Externally Awarded" or "Internally Disbursed" (shown on the profile page) to your Research Finance Administrator. Your can find your Research Finance Administrator at https://www.ucl.ac.uk/finance/research/rs-contacts.php by entering your department
Please report any queries concerning the student data shown on the profile page to:

Email: portico-services@ucl.ac.uk

Help Desk: http://www.ucl.ac.uk/ras/portico/helpdesk
Publication Detail
A presynaptic action of glutamate at the cone output synapse.
  • Publication Type:
    Journal article
  • Publication Sub Type:
    Journal Article
  • Authors:
    Sarantis M, Everett K, Attwell D
  • Publication date:
  • Pagination:
    451, 453
  • Journal:
  • Volume:
  • Issue:
  • Status:
  • Country:
  • Print ISSN:
  • Language:
  • Keywords:
    Animals, Feedback, Glutamates, Glutamic Acid, Ion Channels, Membrane Potentials, Photoreceptor Cells, Receptors, Glutamate, Receptors, Neurotransmitter, Sodium, Synapses, Urodela
Neurotransmitter release from many central nervous system synapses is regulated by 'autoreceptors' at the synaptic terminal, which bind the released transmitter and alter release accordingly. The photoreceptors of lower vertebrates are thought to use glutamate as a neurotransmitter. Glutamate conveys the visual signal to postsynaptic bipolar and horizontal cells, but has been reported not to act on the photoreceptors themselves. We show here that glutamate evokes a current, carried largely by chloride ions, in cones isolated from the tiger salamander retina. This response is localized to the synaptic terminal of the cone. Removing external sodium blocks this action of glutamate. These results suggest the existence of a positive feedback loop at the cone output synapse: over most of the light-response range, glutamate released by depolarization of the cone will cause further depolarization, increasing the gain of phototransduction. Glutamate released from rods may also polarize cones, modulating the gain of the cone output synapse. This system is surprisingly different from the autoreceptor systems for most other transmitters, which act in a negative feedback way.
Publication data is maintained in RPS. Visit https://rps.ucl.ac.uk
 More search options
UCL Researchers
Neuro, Physiology & Pharmacology
University College London - Gower Street - London - WC1E 6BT Tel:+44 (0)20 7679 2000

© UCL 1999–2011

Search by