ИСТИНА

Neuropathy target esterase (NTE) is a toxicologically significant enzyme that was shown to be a biochemical marker for screening of organophosphates (OPs) with respect to their ability to result in organophosphate-induced delayed neuropathy (OPIDN). The inhibition/aging of neuronal NTE within hours of exposure to OP predicts potential for the development of OPIDN after a delay of 1-3 weeks. Human exposure to neuropathic OPs might be detected by monitoring lymphocyte NTE. Biochemical analysis of neuropathy target esterase (NTE) and its inhibitors is based on the combination of the NTE-catalyzed hydrolysis of phenyl valerate and phenol detection by a tyrosinase biosensor. The use of the tyrosinase electrode improvews 10-fold the sensitivity of NTE detection in comparison with a spectrophotometric method. The tyrosinase biosensor was found to be suitable for measurements in whole human blood where spectrophotometric detection is considerably restricted. The specificity of NTE in blood for mipafox and diisopropyl fluorophosphate was close to that for neuronal and lymphocyte NTE. The NTE-like activity in blood was determined to be 0.19 +/- 0.02 mmoles/min per mg of protein. These results are promising for the development of monitoring system that could be routinely used for individuals potentially exposed to neuropathic OP.