Adrenergic Agonists: Direct and Indirect Mechanisms
24 Questions
2 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the main reason why catecholamines administered orally are ineffective?

  • They are quickly metabolized by MAO and COMT. (correct)
  • They cause vasoconstriction in blood vessels.
  • They cannot cross the blood brain barrier.
  • They cause mydriasis.
  • Which characteristic of noncatecholamines allows them to have longer half-lives compared to catecholamines?

  • They do not undergo rapid degradation by MAO and COMT. (correct)
  • They can cause vasoconstriction in blood vessels.
  • They are substrates for COMT.
  • They are polar and cannot cross the blood brain barrier.
  • At low doses, which adrenergic agonist acts primarily on B2 receptors only?

  • Isoproterenol
  • Epinephrine
  • Albuterol (correct)
  • Dopamine
  • What is the main adverse effect of alpha-1 receptor activation?

    <p>Tachycardia</p> Signup and view all the answers

    What is the clinical significance of activation of alpha-2 receptors in the central nervous system?

    <p>Relief of severe pain.</p> Signup and view all the answers

    What is the primary therapeutic application of B1 agonists?

    <p>Stimulation of the heart.</p> Signup and view all the answers

    What is a potential adverse effect of B2 receptor activation in the uterus?

    <p>Hyperglycemia</p> Signup and view all the answers

    What effect does activation of dopamine receptors have on renal vasculature?

    <p>Renal vasodilation</p> Signup and view all the answers

    What is the primary reason why albuterol is considered highly selective when acting at low doses?

    <p>It has minimal impact on the heart rate.</p> Signup and view all the answers

    Which receptor activation leads to relief of severe pain?

    <p>Alpha-2 receptors</p> Signup and view all the answers

    What is the primary therapeutic application for activation of B2 receptors in the uterus?

    <p>Treatment of preterm labor.</p> Signup and view all the answers

    What can overstimulation of B1 receptors lead to in some cases?

    <p>Tachycardia</p> Signup and view all the answers

    Which type of adrenergic agonists work by promotion of norepinephrine release, blockade of norepinephrine reuptake, and inhibition of norepinephrine inactivation?

    <p>Indirect agonists</p> Signup and view all the answers

    What is the main difference between catecholamines and noncatecholamines?

    <p>Their availability for oral use</p> Signup and view all the answers

    Why are catecholamines unable to cross the blood-brain barrier?

    <p>As they contain a catechol group and an amine group</p> Signup and view all the answers

    Which enzyme quickly metabolizes catecholamines?

    <p>Monoamine oxidase [MAO]</p> Signup and view all the answers

    What is the defining feature of indirect adrenergic agonists?

    <p>Their promotion of norepinephrine release</p> Signup and view all the answers

    What is the chemical structure that characterizes catecholamines?

    <p>A benzene ring with hydroxyl groups on two adjacent carbons</p> Signup and view all the answers

    Why do catecholamines have a brief duration of action?

    <p>Due to their chemical structure</p> Signup and view all the answers

    Which class of adrenergic agonists includes dopamine, epinephrine, isoproterenol, and ephedrine?

    <p>Catecholamines</p> Signup and view all the answers

    What do noncatecholamines have in common?

    <p>They cannot cross the blood-brain barrier</p> Signup and view all the answers

    What is the main difference between direct and indirect adrenergic receptor activation?

    <p>Mechanism of action</p> Signup and view all the answers

    What property prevents chatecholamines from being used orally?

    <p>Their chemistry</p> Signup and view all the answers

    Why are chatecholamines unable to act in the central nervous system?

    <p>Due to their chemistry</p> Signup and view all the answers

    More Like This

    Adrenergic Agonists Quiz
    24 questions
    Pharmacology of Adrenergic Agonists Part 1
    18 questions
    Use Quizgecko on...
    Browser
    Browser