David
R. Lynch, M.D.
Assoc Professor of Neurology and
Pediatrics
502 Abramson
University of Pennsylvania
Philadelphia, PA 19104
215-590-2242/fax 215-590-3779
email: lynch@pharm.med.upenn,edu
Click here for selected publications since Dr. Lynch's arrival at Penn
RESEARCH INTERESTS
NMDA receptors
RESEARCH TECHNIQUES
Molecular biology
RESEARCH SUMMARY
Excitotoxicity is a unique pathophysiological mechanism which is involved
in cerebral ischemia, secondary damage in neuronal trauma, and neuronal
damage from prolonged seizures. The deleterious effects from excitotoxicity
result from calcium entry through a specific glutamate receptor, the N-methyl
D-aspartate (NMDA) receptor. NMDA receptor antagonists act both as neuroprotective
agents against excitotoxicity and as anticonvulsants in animals, but human
clinical trials with the most potent agents have been complicated by side
effects including psychosis. Much evidence indicates the presence of multiple
types of NMDA receptors in the brain, and evidence from our laboratory
suggests that different subtypes play different roles in physiological
and excitotoxic processes. If one could develop therapeutic agents which
are selective for the subtypes involved in excitotoxicity, one could more
readily utilize NMDA receptor antagonists for treatment of human diseases.
We use a systematic approach to examine the subtype specific physiological
and pharmacological properties of NMDA receptors. NMDA receptors are created
in tissue culture expression systems, and their properties are studied
biochemically, pharmacologically and physiologically to correlate receptor
properties in these systems with such properties in vivo. We have previously
shown that different NMDA receptor subtypes have distinct pharmacologies
and produce different changes in intracellular calcium. In the near future
we will extend these examinations of subtype specific properties to include
the modulation of other intracellular messengers such as nitric oxide
and examine the effect of such properties on excitotoxicity. Combined
with our studies on the pharmacological specificity of NMDA receptor subtypes,
this will facilitate the development of therapeutic agents directed to
those NMDA receptors which play crucial roles in excitotoxicity.
KEY WORDS:
glutamate, receptor
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