Lymphocyte glutamate dehydrogenase activity in normal aging and neurological diseases.

The activity of total and heat-stable glutamate dehydrogenase (GDH) in lymphocytes increased with aging in 40 control subjects (p less than 0.001). The total GDH activity was lower in patients with olivopontocerebellar atrophy (OPCA), motor neuron disease, Parkinson's disease or Alzheimer's disease than in age-matched control subjects, but not in patients with nondegenerative neurological diseases. The decrease in heat-stable GDH activity was observed in patients with OPCA, Parkinson's disease or Alzheimer's disease, but heat-labile GDH was decreased only in patients with OPCA.