MAPIISG1 - Integrated System for Blood Pressure Regulation Flashcards
What is the purpose of long-term regulation of BP/Kidneys?
based on maintaining homeostatis of body fluid volume
An increase in extraceullar fluid leads to
increase in blood volume and therefore blood pressure
What is the bodys normal response to excess extracellular fluid?
kidneys excrete and decrease blood pressure
What happens to the mechanism with a decrease in blood volume?
decrease in blood pressure so mechanism reverses
What does Excesive Na+ intake result in?
increase H2O retention so increase in BP
What is pressure diuresis?
renal output of H2O
What is pressure natriuresis?
renal output of Na+
According to the renal output curve, over long term water and salt intake must equal
output, demonstrated at equilibrium point of curve
What are two determinants of long–term arterial pressure?
Location of renal output curve (shift
Level of intake/output line (x normal)
How does the kidney control blood pressure?
via renin-angiotensin system
What is the the result of a decrease in Blood Pressure on kidneys?
renin is released from kidneys to bloodstream
What is the result of renin?
reinin substrate (angiotensinogen) is converted to Angiontensin I
What happens to Angiotensin I?
it is converted to Angiotensin II
What direct effect does Angiontensin II have?
It is a powerful vasoconstrictor that will increase retention of salt/H2O, vasoconstrict which increases arterial pressure and increases blood pressure
What indirect effect does Angiotensin II have?
causes adrenal glands to secrete aldosterone which increases salt/water reabsorption by kidneys
