ABSTRACT
Considerable amounts of glutamate dehydrogenase (GDH) activity are known to be present in the mammalian brain. Developmental studies have shown that GDH activity increases in the brain postnatally; these changes parallel the increase in brain glutamate content and nerve terminal growth. Glutamate is thought to serve as the main excitatory transmitter in mammalian nervous tissue. The systemic administration of the compound to rats has resulted in selective destruction of neurons located in the inferior olives, lower cranial nerve nuclei, pons, and substantia nigra. Because the histopathology produced by the toxic agent is similar to that found in patients with olivopontocerebellar degeneration (OPCA). Although the index case of GDH deficiency was a sporadic occurrence, subsequent studies indicated the familiar incidence of the disorder. The OPCAs encompass a number of heterogenous neurodegenerative disorders that share common pathologic features, such as atrophy of the cerebellar cortex, inferior olives, olivocerebellar fibers, basis pontis, and transverse pontine fibers.
