Toxicology Exam 1

  1. Unsaturated lipids are subject to
    peroxidation which may lead to degredation of the lipid membrane
  2. Mechanisms of toxicity to Nucleic Acids
    • Deletion of a part of a nucleotide
    • Cross-linking of nucleotides
    • Alkylation of nucleotides
  3. Deletion of part of a nucleotide may be incurred by
    nitrous acid which deletes amino groups
  4. Cross-linking of nucleotides may result from
    ionizing radiation
  5. Alkylation of nucleotides may result from
    mustard gas
  6. Toxins become bad when
    the body's ability to repair the errors is overwhelmed by toxicities
  7. Portal vein delivers ___ % of blood to the liver and ___ % of the oxygen
    • 75% of blood to liver
    • 25% of oxygen
  8. Hepatic artery delivers ____% of blood to the liver and ____ % of oxygen
    • 25% of blood
    • 75% of oxygen
  9. Periportal area consists of
    area around hepatic artery, portal vein and bile duct entry points
  10. peri-central area or central lobular area
    area around the central vein
  11. Sub-lobular areas
    peri-central and peri-portal areas
  12. Mid-zonal areas
    areabetween the peri-portal and peri-central areas
  13. Classifications of hepatotoxins
    • periportal hepatotoxins
    • pericentral hepatotoxins
    • midzonal area hepatotoxins
  14. Periportal hepatotoxin
    allyl alcohol
  15. Specific inhibitor of alcohol dehydrogenase
    methylpyrazole (4-MP)
  16. Concentrations of allyl alcohol are higher in the periportal area because
    this is where it enters the liver
  17. Acrolein is a metabolite of _____ which causes toxicity in the _____
    • allyl alcohol
    • periportal area
  18. ____ is a contributing factor to allyl alcohol toxicity
  19. Acrolein causes____and requires ____.
    • lipid peroxidation
    • oxygen
  20. Toxins to the pericentral/central lobular area
    • acetaminophen
    • carbon tetrachloride
  21. First important step in APAP induced hepatotoxicity
    Metabolism by CYP450
  22. Activity of CYP450 enzymes is induced by
  23. Mid-zonal toxin
  24. Genotoxic carcinogens
    direct interacton with DNA that leads to cancer
  25. non-genotoxin
    cause cancer by other machanisms rather than direct DNA interaction
  26. Non-genotoxic causes
    • virus
    • high fat diets
    • radiation
    • hormones
    • chemical agents
  27. Inorganic chemical carcinogens
    • arsenic
    • cadmium
  28. Organic chemical agents
    alkylating agents
  29. chemical which upon one or more metabolic steps may interact with DNA leading to cancer
    Procarcinogen or precarcinogen
  30. Chemical that is reactive in nature and directly attacks DNA
    ultimate carcinogen or primary carcinogen
  31. Chemical that is 1 step of biotransformation from being an ultimate carcinogen
    proximate carcinogen
  32. Chemical that by itself does not cause cancer but enhances the carcinogenicity of a carcinogen
  33. Mechanisms of a co-carcinogen
    • enhance production of ultimate carcinogen from a proximate or procarcinogen
    • may interfere with the ability of the body to detoxify the carcinogen
    • could be both
  34. Prevents the activity of a carcinogen
  35. Stages from exposure to a carcinogen to cancer
    • initiation
    • promotion
  36. Initiation
    • naive cell exposed to ultimate carcinogen
    • clinically unrecognizable
  37. Fixation
    when daughter cells inherit the mutated traits
  38. Promotion
    • clinically recognizable
    • effected by a promotor
  39. Effects of a promotor may be caused by
    • the same compound that started it all (initiator)
    • could be a completely differenc compound
  40. 2 ways for promotion to occur
    • complete carcinogen
    • incomplete carcinogen
Card Set
Toxicology Exam 1
Dr. Badr's 2nd Lecture