Abstract

The research program continues to be a study of synaptic mechanisms that operate in the outer synaptic layer of the vertebrate retina. Projects will be continued on calcium-dependent transmitter release, carrier- mediated transmitter release, and the modulation of electrical transmission. Projects related to synaptic transmission are: 1. Compare the voltage dependence of the calcium current in photoreceptors with the voltage dependence of exocytosis. 2. Determine the spatial distribution for calcium entry into a photoreceptor inner segment during depolarization. 3. Determine the Ca-dependence and voltage-dependence for the transfer of information in each direction across the reciprocal synapse between a cone and a horizontal cell. 4. Determine the Ca- dependence for the transfer of information at basal synapses between adjacent cones. 5. Determine the Ca-dependence and voltage-dependence for the transfer of information at basal synapses between cones and bipolar cells. 6. Characterize the modulation by cyclic AMP and cyclic GMP of gap junction channels that connect horizontal cells. In addition, the technology for optically imaging the activity of many cells simultaneously will be developed. 7. The pathway of activity from a photoreceptor to the ganglion cells will be compared for a stimulus that begins in a rod or in a cone. Cellular activity will be imaged with dyes sensitive to intracellular ion concentrations and membrane voltage using a confocal microscope and digital image processing.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Method to Extend Research in Time (MERIT) Award (R37)
Project #
2R37EY002440-12
Application #
3483942
Study Section
Visual Sciences B Study Section (VISB)
Project Start
1982-03-01
Project End
1994-08-31
Budget Start
1989-09-01
Budget End
1990-08-31
Support Year
12
Fiscal Year
1989
Total Cost
Indirect Cost

  Institution

Name
University of Chicago
Department
Type
Schools of Medicine
DUNS #
225410919
City
Chicago
State
IL
Country
United States
Zip Code
60637

  Publications

Rieke, F; Schwartz, E A (1996) Asynchronous transmitter release: control of exocytosis and endocytosis at the salamander rod synapse. J Physiol 493 ( Pt 1):1-8
Cammack, J N; Schwartz, E A (1996) Channel behavior in a gamma-aminobutyrate transporter. Proc Natl Acad Sci U S A 93:723-7
Rieke, F; Schwartz, E A (1994) A cGMP-gated current can control exocytosis at cone synapses. Neuron 13:863-73
Cammack, J N; Rakhilin, S V; Schwartz, E A (1994) A GABA transporter operates asymmetrically and with variable stoichiometry. Neuron 13:949-60
Schwartz, E A (1993) L-glutamate conditionally modulates the K+ current of Muller glial cells. Neuron 10:1141-9
Cammack, J N; Schwartz, E A (1993) Ions required for the electrogenic transport of GABA by horizontal cells of the catfish retina. J Physiol 472:81-102
DeVries, S H; Schwartz, E A (1992) Hemi-gap-junction channels in solitary horizontal cells of the catfish retina. J Physiol 445:201-30
Schwartz, E A; Tachibana, M (1990) Electrophysiology of glutamate and sodium co-transport in a glial cell of the salamander retina. J Physiol 426:43-80
DeVries, S H; Schwartz, E A (1989) Modulation of an electrical synapse between solitary pairs of catfish horizontal cells by dopamine and second messengers. J Physiol 414:351-75
Schwartz, E A (1987) Depolarization without calcium can release gamma-aminobutyric acid from a retinal neuron. Science 238:350-5

Showing the most recent 10 out of 12 publications