Local & Humoral Control of Tissue Blood Flow

  1. What is the short-term autoregulatory control of blood flow?
    Rapid change in vasodilation or vasoconstriction
  2. What is the long-term autoregulatory control of blood flow?
    Slow changes in physical size and number of vessels supplying the tissues
  3. What happens to tissue blood flow if you increase the rate of metabolism?
    Increases blood flow
  4. What happens to tissue blood flow if you increase the arterial oxygen saturation?
    Decreases blood flow
  5. What is the vasodilator theory?
    Greater rate of metabolism, or less oxygen, leads to formation of vasodilator substances
  6. What is the effect of PO2 in metabolic control of blood flow?
    As PO2 increases, blood flow decreases (vasoconstriction)
  7. What is the effect of PCO2 in metabolic control of blood flow?
    As PCO2 increases, blood flow increases (vasodilation)
  8. What is the effect of pH in metabolic control of blood flow?
    As pH decreases, blood flow increases (vasodilation)
  9. What is the effect of adenosine in metabolic control of blood flow?
    As adenosine increases, blood flow increases (vasodilation)
  10. What is the effect of K+ in metabolic control of blood flow?
    As K+ increases, blood flow increases (vasodilation)
  11. Describe the contribution of myogenic tone to blood flow regulation
    Stretching of a vessel causes a counter reaction resulting in blood flow going back to normal
  12. What is hyperemia?
    Excess of blood in a part of the body
  13. What is reactive hyperemia?
    Hyperemia in a tissue after temporary occlusion of an artery
  14. What is active hyperemia?
    Hyperemia following increased tissue metabolic activity
  15. What is the effect of nitric oxide on vessels?
    Major vasodilator
  16. Nitric oxide is AKA ___________________
    Endothelium-derived relaxing factor
  17. Describe the chemistry behind why nitric oxide is a vasodilator
    • O2 + arginine --> NO
    • NO activates soluble guanylate cyclase, which converts cGTP into cGMP
    • cGMP causes vascular smooth muscle relaxation
  18. What are the mechanisms of vascular remodeling in response to chronic increased blood pressure?
    • Inward eutrophic remodeling
    • Hypertrophic remodeling
  19. What are the mechanisms of vascular remodeling in response to chronic increased blood flow?
    • Outward remodeling
    • Outward hypertrophic remodeling
  20. What is inward eutrophic remodeling?
    • Lumen diameter decreases, and vascular wall becomes thicker
    • Total cross-sectional area doesn’t change
  21. What is hypertrophic remodeling?
    Increase in thickness and cross-sectional area of vascular wall
  22. What are the humoral (extrinsic) vasoconstricting agents?
    • NE
    • EPI
    • Angiotensin II
    • Vasopressin
  23. What are the humoral (extrinsic) vasodilating agents?
    • Bradykinin
    • Histamine
  24. Which of the following control mechanisms dominates in the CNS? Intrinsic, neural, or humoral?
    Intrinsic
  25. Which of the following control mechanisms dominates in the coronary vessels? Intrinsic, neural, or humoral?
    Local
  26. Which of the following control mechanisms dominates in the splanchnic circulation? Intrinsic, neural, or humoral?
    Intrinsic and humoral
  27. Which of the following control mechanisms dominates in cutaneous blood flow? Intrinsic, neural, or humoral?
    Neural
  28. Which of the following control mechanisms dominates in skeletal muscle? Intrinsic, neural, or humoral?
    Local
Author
stepha998
ID
344655
Card Set
Local & Humoral Control of Tissue Blood Flow
Description
ATSU
Updated