Lymphocyte esterases and hydroxylases in neurotoxicology.

Certain human lymphocytic enzymes, such as neuropathy target esterase (NTE), have become useful markers in clinical toxicology. NTE has been proposed as a predictive marker in organophosphate poisoning for the subsequent development of organophosphate-induced delayed neuropathy. We studied lymphocyte aryl hydrocarbon hydroxylases, and using a differential method based on that of NTE employing a phenyl-alkanoic substrate, developed an enzyme assay for use in toxic neuropathies.

Effect of dietary alpha-linolenic acid deficiency on habituation.

Three weeks before mating, two groups of SWISS OF1 mice were fed a diet that was similar but contained either peanut oil poor in alpha-linolenic acid [18:3(n-3)] (n-3 deficient = deficient mice = (n-3)-) or peanut + rapeseed oil rich in alpha-linolenic acid (n-3 nondeficient = controls = (n-3)+). Pups, fed the same diet as their dams, aged 45 to 62 days were used for brain lipid analysis and for behavioral experiments, aimed at determining whether there is a relation between the dietary intake of alpha-linolenate and a simple form of learning: habituation. The behavior of mice was compared using four models: exploration recorded in a photocell actimeter, activity in an open-field, duration of immobility in the forced swimming test and number of escape attempts from a small closed space.

[Lymphocyte phenylvaleric acid hydroxylase activity (L-PVH), a new marker of peripheral neurotoxicity].

A reduction in the level of a new enzymatic assay--a phenyl valerate hydrolase (PVH)--has been found during the clinical evolution of toxic neuropathies (as almitrine-bismetilate ones) as well as alcoholic or diabetic neuropathies. The substrate and the enzymatic function are different from those used by M.K.

[Determination of the neurotoxic esterase in neurologic pathology of toxic origin. Measurement in human lymphocytes in poisoning by organophosphates, ciguatera and ethyl alcohol].

Lymphocytic NTE activity was measured after intoxication by organo phosphorus compounds and in chronic alcoholics at the beginning of alcohol withdrawal. The results showed a rapid fall in lymphocytic NTE activity; neuropathy developed when the inhibition was 75 p. 100 or more.