The role of neurotransmitters and indicators of oxidative stress in the formation of disorders of central conductive structures in patients who came into contact with metallic mercury

Introduction. Studies of toxic lesions due to exposure to metallic mercury compounds do not allow us to identify the features of the violation of central afferent conducting structures in the long-term period of chronic mercury intoxication (CHMI). The contribution of various systems to the development of pathology is not sufficiently disclosed.

The study aims to identify the role of neurotransmitters in pathological changes in central hemodynamics, the value of lipid peroxidation products and the activity of antioxidant protection in the demyelination of central afferent conductive structures in workers exposed to metallic mercury in the workplace.

Materials and methods. The authors examined 47 people (group one) — trained chemical production workers exposed to metallic mercury, and group two (51 people) — patients in the long-term period of CHMI. The control group (CG) consisted of 30 people who had no contact with toxicants. We have determined concentration of neurotransmitters, lipid peroxidation products (LPP), superoxide dismutase (SOD) and reduced glutathione (RG), nitric oxide.

Results. Experts observed statistically significant changes in indicators in subgroups with and without changes in cerebral hemodynamics and in group two when compared with group one. Comparison of persons with CHMI without changes in blood circulation with the presence of disorders revealed an increase in normetanephrine in the latter, a decrease in NT-3. Correlation analysis showed: in group one, there was a statistically significant difference between the vasomotor reactivity index (VRI) and serotonin. In group two — between CHMI and serotonin, adrenaline and dopamine. Changes in afferent pathways are interrelated with indicators of oxidative stress. Violations are accompanied by the formation of a pathological system, are signs of dysregulatory pathology.

Limitations. The disadvantage of the study is the fact that scientists determined the content of neurotransmitters and products of lipid peroxidation and antioxidant protection in the blood of the subjects, and not in the structures of the brain.

Conclusion. The increased content of biogenic amines leads to a change in peripheral blood circulation and regulation of cerebral blood flow by pressor action on the regulation of the vascular bed, leading to vasoconstriction, changes in the bioelectric activity of the structures of the reticular formation of the midbrain, hypothalamus, thalamocortical structures, most pronounced in the long-term period of chronic mercury intoxication. We found that the formation of demyelination in patients with chronic mercury intoxication was accompanied by a decrease in the concentration of NT-3. It was natural to reduce the level of reduced glutathione and superoxide dismutase in neurodegenerative processes in trained workers exposed to metallic mercury at work, and in patients with a long period of chronic mercury intoxication.

Ethics. The study was conducted in compliance with the principles of the Helsinki Declaration of the World Association "Ethical principles of conducting Scientific medical research with human participation" (as amended in 2008), "Rules of Clinical Practice in the Russian Federation" (approved by the Order of the Ministry of Health of the Russian Federation dated 06/19/2003 No. 266).

Contribution:
Rusanova D.V. — concept and design of the study, collection and processing of material, writing and formatting of the article, editing;
Lakhman O.L. — concept and design of research, editing;
Kudaeva I.V. — collection and processing of material, writing and formatting of the article;
Kuptsova N.G. — collection and processing of the material, writing and formatting of the article.
All co-authors — approval of the final version of the article, responsibility for the integrity of all parts of the article.

Funding. The financing was carried out within the framework of the State Task on fundamental and Exploratory scientific research. The study had no funding.

Conflict of interests. The authors declare that no conflict of interests.

Received: 01.11.2022 / Accepted: 17.11.2022 / Published: 23.12.2022

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