How does the renal-body fluid system normalize arterial pressure if blood volume increases?
Blood volume increases --> arterial pressure increases --> kidneys excrete excess volume --> arterial pressure back to normal
How does the body normalize blood pressure if blood volume increases?
Increase pressure diuresis
How does sodium balance affect arterial pressure?
Higher sodium higher arterial pressure, because excess salt reduces the ability of kidneys to excrete fluid, more blood volume = higher arterial pressure
How does the renin-angiotensin-aldosterone system maintain blood pressure?
Sodium retention by kidneys
Aldosterone release from the adrenals to increase renal sodium/water retention
Activation of the heart and vasoconstriction
Describe the renin-angiotensin-aldosterone system (RAAS) pathway
Angiotensinogen --> angiotensin I --> angiotensin II --> AT1 receptor --> kidneys, adrenal grand, heart, vessels, brain
What does renin do?
Converts angiotensinogen to angiotensin I
What does a renin inhibitor do?
Blocks angiotensinogen from being converted to angiotensin I
What does ACE I do?
Converts angiotensin I to angiotensin II
What does an ACE inhibitor do?
Blocks angiotensin I from being converted to angiotensin II
What does an AT1 receptor blocker do?
Blocks AT1 receptors in kidney, adrenal gland, heart, vessels, and brain
What effects does angiotensin II have on vessels and kidneys and for what reason?
Renal retention of salt and water
To increase arterial pressure
What does angiotensin II do to blood pressure?
Describe the body’s response to an increased salt intake and how it regularizes blood pressure, increased salt intake -->
Increased salt intake --> increased extracellular volume --> increased arterial pressure --> decreased renin and angiotensin --> decreased renal retention of salt and water --> extracellular volume almost back to normal --> arterial pressure almost back to normal
What is pressure natriuresis?
Increases in renal perfusion pressure lead to decreases in sodium reabsorption and increases in sodium excretion
What is the effect of constricting the renal artery of one kidney after the other kidney has been removed?
Systemic arterial pressure increases
Renin secretion decreases
Essential chronic hypertension is characterized by…
Elevated mean arterial pressure and total peripheral resistance
Renal-blood volume pressure controls and RAAS are slow/fast and typically acute/chronic
Compare renal and neural control of blood pressure