Regional Circulations/Microcirculation Flashcards
Atrial natriuretic peptide
Causes excretion of Na and water also causes vasodilation decrease TPR
Angiotensin II
Potent vasoconstrictor, simulations aldosterone synthesis and release for retention of Na
Epinephrine
vasodilation in live and skeletal muscle, increases HR
Nitric Oxide
Vascular relaxation, short half life, vasodilator
Endothelin (ET-1)
potent vasoconstrictor
Which part of the heart is at greatest risk for ischemic damage?
Endocardium
What equation is a measure of myocardial consumption?
Rate-pressure product (RRP) = HR * SystolicBP
What is autoregulation?
A control mechanism that ensures that an organ gets the proper blood flow/oxygen supply.
How much of the blood supply goes to splanchnic circulation?
~25% at rest, but can elevate quickly after a meal. Splanchnic circulation is set up in parallel and series
What kind of exchange happens in the intestinal villi?
Counter current exchange, allowing venuole to steal oxygen from ateriole, which in low flow condictions can cause anoxic damage to the villi
What does vascoconstriction do to thermoregulation?
Retain heat, causing body/feet/hands cold to the touch
How does vasodilation effect thermoregulation?
Vasodilation, sweat
What is reactive hyperemia?
Interruption of blood flow for a period of time allows buildup of vasodilating metabolites, when flow is resumed, blood flow markedly increases due to the vasodilation and eventually returns to normal.
What is most useful in controling cerebral blood flow?
Partial pressures of CO2 rather than O2
How is the effects of constrained space in the brain related to mean arterial pressure?
Cerebral perfusion pressure (CPP) = MAP - ICP
