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Modes of action of toxic agents

E W Maynert, B G Hammond

    Annals of Clinical and Laboratory Science
    |July 1, 1976
    PubMed

    Insights

    Toxic agents act by forming chemical bonds with tissue targets, disrupting cellular functions. Understanding these toxic mechanisms, from ionic interactions to covalent binding, is key to explaining diseases like cancer.

    Area of Science:

    • Toxicology
    • Biochemistry
    • Molecular Biology

    Background:

    • Toxic agents exert harmful effects through diverse biochemical interactions.
    • The nature of chemical bonds formed between toxicants and biological targets dictates the toxicological outcome.
    • Understanding these interactions is crucial for explaining various disease pathologies.

    Purpose of the Study:

    • To elucidate the principal modes of action of toxic agents.
    • To correlate toxicant mechanisms with the type of chemical bond formed.
    • To illustrate toxic processes using examples of chemical-induced diseases.

    Main Methods:

    • Review and discussion of established toxicological principles.
    • Categorization of toxic actions based on chemical bonding (ionic, van der Waals, coordinate-covalent, covalent).
    • Illustration of mechanisms with examples of chemicals causing necrosis, allergy, and cancer.

    Main Results:

    • Toxic agents interact with tissues via ionic, van der Waals, coordinate-covalent, and covalent bonds.
    • Specific examples include enzyme inhibition, nucleic acid intercalation, and electrolyte imbalance.
    • Covalent binding involves antimetabolites, electrophiles, or free radicals, leading to cellular damage.

    Conclusions:

    • The type of chemical bond formed is central to the mechanism of toxicity.
    • Diverse molecular interactions underlie toxic effects, ranging from functional alterations to structural damage.
    • These mechanisms explain the pathogenesis of chemically induced diseases such as cancer and necrosis.

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