Renal Physiology And Bp:Natriuretic Peptides Flashcards
Bp=
CO x TPR
CO=
SV x HR
What happens when you increase fluid volume?
Increase stroke volume which will increase cardiac output and therefore bp= increase flow of blood through the kidneys,increasing glomerular filtration rate
Prolonged periods of blood pressure can have what effect on the kidney?
Lead to damage in the kidneys
E.g. proteins being passed through when they shouldn’t
Release of natriuretic peptides in response to increase in CO? Have what effect ?
Increase production of urine to decrease SV
Vasodilation to reduce TPR
= overall will reduce CO, TPR AND BP
Natriuretic peptides define
Hormones released from the atria and ventricles in the heart in response to increased stretch of the heart
In healthy individual , increase in CO sensed by?
BARORECEPTORS In the heart
Types of Natriuretic peptides
Atrial Natriuretic peptide (ANP)
Brain Natriuretic peptide (BNP)
Natriuretic peptide receptors respond to what peptides? And mechanism
Respond to ANP and BNP
The receptors are linked to a Guanylate Cyclase enzyme: converts GTP to cyclic GMP which stimulates Protein Kinase A = causes vasodilation similar to PKA (activation of ion channels/ inhibition of contractile proteins )
Other function of Natriuretic peptide despite vasodilation?
Act to decrease Na reabsorption in the nephron: through inhibition of ENaC = which increase urine output
PROMOTES diuresis and naturesis
Natiuresis by Natriuretic peptides
Inhibits reabsorption of sodium in collecting duct and other segments of the nephron, increase Sodium excretion in the urine
= Lower SV
Diuresis by Natriuretic peptides
ANP dilates afferent arteriole + Vasodilating effects increase blood flow which will also increase excretion of urine
= lower sv
