Comparative study of manifestations of intoxication with reversible cholinesterase inhibitors

Introduction. Reversible cholinesterase inhibitors include compounds with different structures and effects on the body, which requires additional research.

The aim of the work is a comparative study of the manifestations of convulsive syndrome in an experiment on animals, using various cholinesterase inhibitors as model toxicants.

Material and methods. A comparative study of the manifestations of convulsive syndrome was conducted with a single intraperitoneal administration of Phenylcarbamate, 1 mg/kg, Galantamine, 25 mg/kg, and Tacrine, 15 mg/kg to rats.

Results. Differences in the latent period of onset and duration of seizure syndrome between all groups were revealed. Statistically significant differences in the parameters of motor activity, neuromotor and cognitive functions were not established. According to the results of histological examination after exposure to Phenylcarbamate, Tacrine and Galantamine, individual deviations from the norm were recorded in the hippocampus and cerebral cortex: pronounced expansion of perivascular and pericellular spaces, the appearance of dark and wrinkled neurons.

Limitations. The number of animals used in the study was in accordance with bioethical principles and the requirement for a sufficient number of animals for statistically reliable results: 10 animals in each group.

Conclusion. It has been established that reversible cholinesterase inhibitors can vary significantly in the severity and pathogenetic features of their effects on the body, which must be taken into account when developing treatments for convulsive syndrome.

Compliance with ethical standards. The experiment with animals was performed after a positive conclusion of the bioethical commission of the S.N. Golikov Scientific and Clinical Center of Toxicology (conclusion N 5/23, 20.12.2023).

Authors' contribution:
Belskaya A.V., Melekhova A.S., Melnikova M.V. – conducting scientific research (animal experiments), material processing, text writing;
Bespalov A.Ya. – synthesis of model toxicants;
Gaikova O.N. – conducting a histological examination;
Zorina V.N. – scientific guidance in conducting research, text writing and editing.
All co-authors – approval of the final version of the article, responsibility for the integrity of all parts of the article.

Conflict of interests. The authors declare the absence of obvious and potential conflicts of interest in connection with the publication of this article.

Funding. The study was conducted within the framework of the implementation of the research project code “Provodnik” under the State Project of S.N. Golikov Scientific and Clinical Center of Toxicology (No. 124022400179-8).

Received: April 14, 2025 / Accepted: November 25, 2025 / Published: January 15, 2026

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