The overall goal of the research is to determine how light-evoked signals in the retina are formed and how they are modified by neural activity. The neural image of the visual scene that is processed by the retina and conducted to brain is the result of a complex interplay between excitation and inhibition. One source of inhibition in the retina is the input from horizontal cells onto photoreceptors and bipolar cells; another source is the input from glycinergic and GABAergic amacrine cells onto ganglion cells. In this proposed study the focus will be on characterizing the generation and modulation of inhibitory activity in these two pathways. The general approach is to characterize first the pharmacological and biophysical bases of cell-cell interactions and then incorporate these mechanisms into a more general model. For horizontal cells the study will be directed to investigating the mechanisms by which extracellular neurotransmitters, such as glutamate and GABA, and intracellular second messengers, particularly H+ ions, regulate function. For ganglion cells this project will characterize the action and mechanisms of glycinemediated inhibition in the tiger salamander and mouse retina. The study will utilize patch pipettes to perform voltage-clamp measurements from enzymatically-isolated retinal neurons. These same recording techniques will be used to measure light-evoked responses from neurons in the retinal slice preparation. Intracellular H+ and calcium ion activities will be monitored optically with selective dyes.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Method to Extend Research in Time (MERIT) Award (R37)
Project #
5R37EY001869-21
Application #
2331620
Study Section
Visual Sciences C Study Section (VISC)
Project Start
1977-02-01
Project End
1998-01-31
Budget Start
1997-02-01
Budget End
1998-01-31
Support Year
21
Fiscal Year
1997
Total Cost
Indirect Cost
Name
University of California San Francisco
Department
Ophthalmology
Type
Schools of Medicine
DUNS #
073133571
City
San Francisco
State
CA
Country
United States
Zip Code
94143
Delwig, Anton; Majumdar, Sriparna; Ahern, Kelly et al. (2013) Glutamatergic neurotransmission from melanopsin retinal ganglion cells is required for neonatal photoaversion but not adult pupillary light reflex. PLoS One 8:e83974
Delwig, Anton; Logan, Anne M; Copenhagen, David R et al. (2012) Light evokes melanopsin-dependent vocalization and neural activation associated with aversive experience in neonatal mice. PLoS One 7:e43787
Chen, Albert I; Nguyen, Cindy N; Copenhagen, David R et al. (2011) TrkB (tropomyosin-related kinase B) controls the assembly and maintenance of GABAergic synapses in the cerebellar cortex. J Neurosci 31:2769-80
Johnson, Juliette; Wu, Vincent; Donovan, Michael et al. (2010) Melanopsin-dependent light avoidance in neonatal mice. Proc Natl Acad Sci U S A 107:17374-8
Blankenship, Aaron G; Ford, Kevin J; Johnson, Juliette et al. (2009) Synaptic and extrasynaptic factors governing glutamatergic retinal waves. Neuron 62:230-41
Grishanin, Ruslan N; Yang, Haidong; Liu, Xiaorong et al. (2008) Retinal TrkB receptors regulate neural development in the inner, but not outer, retina. Mol Cell Neurosci 38:431-43
Renteria, Rene C; Tian, Ning; Cang, Jianhua et al. (2006) Intrinsic ON responses of the retinal OFF pathway are suppressed by the ON pathway. J Neurosci 26:11857-69
Duncan, Jacque L; Yang, Haidong; Doan, Thuy et al. (2006) Scotopic visual signaling in the mouse retina is modulated by high-affinity plasma membrane calcium extrusion. J Neurosci 26:7201-11
Krizaj, David; Lai, F Anthony; Copenhagen, David R (2003) Ryanodine stores and calcium regulation in the inner segments of salamander rods and cones. J Physiol 547:761-74
Krizaj, David; Demarco, Steven J; Johnson, Juliette et al. (2002) Cell-specific expression of plasma membrane calcium ATPase isoforms in retinal neurons. J Comp Neurol 451:1-21

Showing the most recent 10 out of 35 publications