The excitatory amino acid (EAA) glutamic acid has a central role in the computer-like signaling that occurs between neurons in the nervous system. It appears to be involved both in signaling on a millisecond time scale and in slower regulatory functions. These diverse actions are mediated by at least four major classes of EAA receptors. One of those classes is the L-2-amino-4-phosphonobutanoic acid (L-AP4) receptor, named for a potent agonist for this receptor. A number of compounds structurally related to L-AP4 have shown promising properties for differentiating the L-AP4 receptor from other EAA receptors and for gaining insight into the features of molecular structure needed for molecules to interact with L-AP4 receptors.
The specific aims of this project are: (1) to synthesize novel structural analogues of L-AP4 in order to develop selective and novel pharmacological agents for differentiating AP4-sensitive biological systems; (2) to evaluate these compounds as agonists for L-AP4 receptors in selected retinal, hippocampal, and spinal neural systems; (3) to seek EAA analogues that act as antagonists for the L-AP4 receptor. Antagonists have proven to be powerful tools for pharmacological studies, but no antagonists are known for L-AP4 receptors; (4) to evaluate novel analogues of L-AP4 for their activity on other EAA receptors and on an EAA transmembrane transport system. This research is intended to provide pharmacological probes of value both for elucidating the underlying biological roles of excitatory amino acid receptors and as possible experimental and therapeutic agents for modifying neuronal signaling. These studies may have significance for understanding mechanisms of neuronal control and plasticity and may also lead to insight into changes of neuronal excitability that occur in disease states such as epilepsy.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
2R01NS017944-07A2
Application #
3397951
Study Section
Neurology B Subcommittee 2 (NEUB)
Project Start
1986-08-01
Project End
1995-02-28
Budget Start
1992-03-01
Budget End
1993-02-28
Support Year
7
Fiscal Year
1992
Total Cost
Indirect Cost
Name
University of Minnesota Twin Cities
Department
Type
Schools of Medicine
DUNS #
168559177
City
Minneapolis
State
MN
Country
United States
Zip Code
55455
Roon, R J; Koerner, J F (1996) Persistent depression of synaptic responses occurs in quisqualate sensitized hippocampal slices after exposure to L-aspartate-beta-hydroxamate. Brain Res 734:223-8
Littman, L; Chase, L A; Renzi, M et al. (1995) Effects of quisqualic acid analogs on metabotropic glutamate receptors coupled to phosphoinositide hydrolysis in rat hippocampus. Neuropharmacology 34:829-41
Chan, P C; Roon, R J; Koerner, J F et al. (1995) A 3-amino-4-hydroxy-3-cyclobutene-1,2-dione-containing glutamate analogue exhibiting high affinity to excitatory amino acid receptors. J Med Chem 38:4433-8
Johansen, P A; Chase, L A; Sinor, A D et al. (1995) Type 4a metabotropic glutamate receptor: identification of new potent agonists and differentiation from the L-(+)-2-amino-4-phosphonobutanoic acid-sensitive receptor in the lateral perforant pathway in rats. Mol Pharmacol 48:140-9
Schulte, M K; Roon, R J; Chalmers, D J et al. (1994) Utilization of the resolved L-isomer of 2-amino-6-phosphonohexanoic acid (L-AP6) as a selective agonist for a quisqualate-sensitized site in hippocampal CA1 pyramidal neurons. Brain Res 649:203-7
Venkatraman, S; Roon, R J; Schulte, M K et al. (1994) Synthesis of oxadiazolidinedione derivatives as quisqualic acid analogues and their evaluation at a quisqualate-sensitized site in the rat hippocampus. J Med Chem 37:3939-46
Price Jr, R H; Schulte, M K; Renno, W M et al. (1994) Immunocytochemical evidence that quisqualate is selectively internalized into a subset of hippocampal neurons. Brain Res 663:317-25
Schulte, M K; Roon, R J; Koerner, J F (1993) Quisqualic acid induced sensitization and the active uptake of L-quisqualic acid by hippocampal slices. Brain Res 605:85-92
Subasinghe, N; Schulte, M; Roon, R J et al. (1992) Quisqualic acid analogues: synthesis of beta-heterocyclic 2-aminopropanoic acid derivatives and their activity at a novel quisqualate-sensitized site. J Med Chem 35:4602-7
Peterson, N L; Kroona, H B; Johnson, R L et al. (1992) Activity of the conformationally rigid 2-amino-4-phosphonobutanoic acid (AP4) analogue (RS)-1-amino-3-(phosphonomethylene)cyclobutane-1-carboxylic acid (cyclobutylene AP5) on evoked responses in the perforant pathway of rat hippocampus. Brain Res 571:162-4

Showing the most recent 10 out of 22 publications