Abstract
Enolase is a dimetric enzyme which catalyses the interconversion of 2-phospho-D-glycerate and phosphoenolpyruvate in the glycolytic pathway. It had three immunologically distinct subunits α, β and γ, giving rise to the five isoenzymes αα, ββ, γγ, αβ and αγ. In the central nervous system γγ and αγ enolases are mainly localized in neuronal cells, so called neuron-specific enolase (NSE). NSE is released into CSF and serum due to damage of the neurvous tissues.
In this study, we examined NSE levels in CSF of 29 patients and sera of 12 patients with cerebral vascular disease and in CSF and sera of 23 patients with other various neurological diseases.
The present study showed a positive correlation between the size of the infarction or hemorrhage measured on the CT scan and the levels of NSE. More interestingly in acute phase of the patients with mild cerebral ischemic attacks including transient ischemic attack (TIA) and minor stroke, the clue of which was not even visualized on CT scan, the levels of NSE in CSF were also high. Although the neurological deficits depended on the size as well as the site of the infarction, the level of NSE was, however, also related to the clinical outcome in this study. The time sequential changes of NSE levels disclosed more higher levels in acute phase than in subacute or chronic phase, because NSE is rapidly cleared from CSF and serum. On the other hand, in the patients with various other neurological diseases, this study showed some correlation between NSE level and the severity of diseases. Especially, the level of patient with Creutzfeldt-Jakob disease was markedly high in the early stage of the disease at which time the brain CT showed no or minimal abnormalities.
In conclusion, this study demonstrated the positive relationship between NSE levels and the extent of tissue damage of nervous system and suggested that NSE is a potentially important marker of the ultra-early and early diagnosis of ischemic cerebral diseases, especially of TIA.
