18 Questions
What is the term for the phenomenon where a drug is conjugated either rapidly or slowly with acetyl-CoA in the human population?
Acetylation polymorphism
Which populations are classified as slow acetylators based on differences in N-acetyltransferase activity?
Egyptians and some Western European groups
Which of the following is NOT true about slow acetylators?
Conjugate drugs with acetyl-CoA rapidly
What is the main cause of acetylation polymorphism in individuals?
Genetic differences in N-acetyltransferase activity
Which of the following drugs exemplifies acetylation polymorphism?
Isoniazid
What is the objective of methylation in the metabolic pathway?
Biosynthesis of endogenous compounds
What type of metabolites does methylation generally not lead to?
Polar or water-soluble metabolites
Which activated coenzyme is involved in methylation reactions?
S-adenosylmethionine (SAM)
Which enzyme carries out O-methylation of important neurotransmitters like norepinephrine and dopamine?
Catechol-O-methyltransferase (COMT)
Which type of methylation do transferases specifically methylating histamine, serotonin, and epinephrine not usually participate in?
Metabolism of xenobiotics
What feature does COMT require for carrying out methylation reactions?
Catecholic functionality
Which phase pathways are drugs and xenobiotics often metabolized by to give several metabolites?
Phase I and phase II pathways
Which enzyme is primarily involved in methylation reactions in the body?
S-adenosylmethionine
Which type of drug derivative undergoes methylation reactions to form methylated products?
Quaternary ammonium derivatives
Which biological factor can affect the activity of methyltransferases and consequently alter drug metabolism?
All of the above
Which factor determines the stereoselectivity of substrates in methylation reactions?
Substrate stereoselectivity
Which factor can lead to the accumulation of toxic levels of a drug due to decreased metabolic elimination?
Decreased enzyme activity
Which factor can decrease the intensity and duration of drug action as well as its efficacy?
Increased rate of metabolism
Test your knowledge on drug metabolism and its impact on pharmacological actions and toxicity. Explore how alterations in drug metabolism can affect the intensity, duration, and potential toxicity of a drug.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
