A common element in local neuronal circuits in the central nervous system (CNS) are dendrodendritic (D-D) synapses. Such neuron to neuron contacts have been implicated to be important in the synchronous firing and lateral inhibition of neurons, phenomena which re important for the normal functioning and pathology of many aspects of the CNS. However, very little is known about the fundamental properties of D-D synapses, which we may expect are very different from more conventional axosomatic or axodendritic synapses. Here we propose a study of the reciprocal D-D synapse between the mitral and granule cells of the rat olfactory bulb, as an example of a D-D synapse in the CNS. Whole-cell patch clamp measurements will be made from visually identified mitral and granule cells.
The specific aims are: (1) to determine the membrane voltage profile at the dendritic release sites; (2) to characterize the fast and slow modulatory effects of the glutamate that is released at this synapse; and (3) to consider how the released glutamate alters the local circuit, lateral inhibitory interactions between mitral cells, which are believed to be important in olfactory sensory information processing.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
5F32DC000270-02
Application #
2608250
Study Section
Special Emphasis Panel (ZRG1-NLS-1 (01))
Project Start
1997-12-01
Project End
Budget Start
1997-12-01
Budget End
1998-11-30
Support Year
2
Fiscal Year
1998
Total Cost
Indirect Cost
Name
Oregon Health and Science University
Department
Neurosciences
Type
Schools of Medicine
DUNS #
009584210
City
Portland
State
OR
Country
United States
Zip Code
97239
Schoppa, N E; Westbrook, G L (1999) Regulation of synaptic timing in the olfactory bulb by an A-type potassium current. Nat Neurosci 2:1106-13
Schoppa, N E; Kinzie, J M; Sahara, Y et al. (1998) Dendrodendritic inhibition in the olfactory bulb is driven by NMDA receptors. J Neurosci 18:6790-802