Chemical Mediators and Vasoactive Amines
14 Questions
0 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 function of Lipoxins?

  • To inhibit neutrophil chemotaxis and adhesion to endothelium (correct)
  • To produce prostaglandins
  • To cause vasodilation and increase vascular permeability
  • To stimulate chemotaxis

    • What is the effect of NSAIDs on Prostaglandins?

  • Enhance the activity of Cyclooxygenase
  • Inhibit the production of Prostaglandins (correct)
  • Have no effect on Prostaglandins
  • Stimulate the production of Prostaglandins

    • What is the effect of Cox2 inhibitors on Cardiovascular events?

  • Have no effect on Cardiovascular events
  • Enhance Platelet aggregation
  • Decrease the risk of Cardiovascular events
  • Increase the risk of Cardiovascular events (correct)

    • Which of the following is NOT a function of Leukotrienes?

    <p>Inhibiting neutrophil chemotaxis</p> Signup and view all the answers

    What is the function of Glucocorticoids in relation to Arachidonic acid metabolism?

    <p>Inhibit Phospholipase activity</p> Signup and view all the answers

    What is the source of Prostacyclin?

    <p>Macrophages and Endothelial cells</p> Signup and view all the answers

    What is the primary function of histamine in the body?

    <p>Vasodilation and increase in vascular permeability</p> Signup and view all the answers

    Which of the following is NOT a characteristic of vasoactive amines?

    <p>Newly synthesized</p> Signup and view all the answers

    What is the primary function of serotonin?

    <p>Neurotransmission and regulation of intestinal motility</p> Signup and view all the answers

    Which enzyme is responsible for the production of prostaglandins and thromboxanes?

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

    What is the primary function of prostacyclin?

    <p>Vasodilation and inhibition of platelet aggregation</p> Signup and view all the answers

    Which cells are responsible for the production of thromboxane?

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

    What is the role of arachidonic acid metabolites in the body?

    <p>Act locally and then decay spontaneously</p> Signup and view all the answers

    What is the primary function of prostaglandins?

    <p>Contribute to pain and fever</p> Signup and view all the answers

    Study Notes

    Chemical Mediators

    • Chemical mediators can be classified into two categories: cell-derived and plasma-derived.

    Cell-Derived Chemical Mediators

    • Preferentially preformed in secretory granules (vasoactive amines).
    • Newly synthesized (arachidonic acid metabolites).

    Vasoactive Amines

    • Histamine:
      • Produced by mast cells.
      • Induces vasodilation and increases vascular permeability.
      • Inactivated by histaminases.
    • Serotonin:
      • Produced by platelets.
      • Induces vasoconstriction.
      • Released during platelet aggregation.
      • Acts as a neurotransmitter and regulates intestinal motility.

    Arachidonic Acid Metabolites

    • Produced by leukocytes, mast cells, and macrophages.
    • Act locally and then decay spontaneously or are enzymatically destroyed.
    • Released from cell membrane phospholipids by the action of phospholipases that have been activated by stimuli or inflammatory mediators.

    Enzymatic Pathway of Arachidonic Acid Metabolites

    • Cyclooxygenase pathway:
      • Stimulates the synthesis of prostaglandins and thromboxanes.
    • Lipoxygenase pathway:
      • Responsible for the production of leukotrienes and lipoxins.

    Prostaglandins

    • Produced from mast cells (majorly) and endothelial cells.
    • Prostacyclin:
      • Produced from endothelial cells.
      • Mediated by COX2.
      • Causes vasodilation and inhibits platelet aggregation.
    • Prostaglandins contribute to the pain and fever that accompany inflammation.

    Thromboxanes

    • Produced from platelets (majorly).
    • Mediated by COX1.
    • Causes vasoconstriction and platelet aggregation.

    Leukotrienes

    • Produced by neutrophils, macrophages, and mast cells.
    • Cause vasodilation, increase vascular permeability, and stimulate chemotaxis.

    Lipoxins

    • Anti-inflammatory mediator.
    • Produced by leukocytes.
    • Inhibit neutrophil chemotaxis and adhesion to endothelium.
    • Serve as endogenous antagonists to leukotrienes.

    Inhibitors of Chemical Mediators

    • Nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit cyclooxygenase activity, blocking all prostaglandin synthesis.
    • Glucocorticoids (steroidal inhibitors) inhibit the activity of phospholipase, preventing arachidonic acid metabolite formation.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    This quiz covers the different types of chemical mediators, including cell-derived and plasma-derived mediators, and their functions in the body, specifically vasoactive amines such as histamine and serotonin.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser