Features and patterns of changes in neurochemical parameters at different stages of chronic mercury intoxication

Abstract

Introduction. At present, the features of the clinical picture and pathogenesis of the formation and progression of chronic intoxication under the influence of mercury remain insufficiently studied. Purpose. To study the features and patterns of changes in the neurotransmitters and neurotrophic factors concentration at different stages of chronic mercury intoxication (CMI). Materials and methods. A cohort examination of 69 workers (group 1) exposed to mercury, 18 individuals in the initial period of CMI (group 2), and 55 patients in the long-term period (group 3) were carried out. The content of neurotransmitters and neurotrophic factors was determined by enzyme immunoassay. The statistical processing included Wilcoxon, Kruskal-Wallis and Mann-Whitney tests. Results. Higher levels of histamine were found in group 2, low levels of metanephrine in group 1, and normetanephrine in group 3. An increase in the BDNF concentration was revealed in group 2 compared with groups 1 and 3. The content of neurotrophin-3 in group 3 was statistically significantly lower than in group 2. Conclusion. The general pattern for all stages is an increase in the norepinephrine and CNTF concentration. Mercury neurointoxication at all stages is characterized by high serotonin levels. A distinctive feature for trained workers is a compensatory increase in the normetanephrine level and a low BDNF and NT-3. For the initial period of CMI, an increase in the histamine, BDNF and NT-3 content is characteristic. The long-term period is characterized by an imbalance in the concentration of the studied neurotransmitters and neurotrophic factors.