Speculations on disease states induced by excitatory amino acids.

There is much current interest in excitatory amino acids and their receptors because of their postulated involvement in several disorders of the nervous system. They function as neurotransmitters, but can act as neurotoxins in some situations. They have been implicated in the pathogenesis of cerebral hypoxic/ischemic and hypoglycemic damage, in epilepsy, in some degenerative diseases, and in some forms of neurotoxin-induced cerebral dysfunction. These diseases may reflect abnormality in a system which has evolved to provide synaptic plasticity essential for learning and memory. The purpose of this paper is to explore the ramifications of such a hypothesis.