Block 10 Renal function and failure

Question 1

State the 3 components of the glomerulus

Answer 1

Epithelium (podocytes)
Basement membrane
Endothelium of blood vessels

Question 2

Describe the effects of ANP on renal function

Answer 2

Increases sodium and water excretion by dilation of glomerular afferent arterioles and constriction of efferent arterioles increasing GFR
Increases blood flow of vasa recta lowering osmolarity leading to less reabsorption

Question 3

Describe the effect of angiotensin II on plasma sodium and water

Answer 3

Sodium and water retention
Constriction of efferent arterioles –> increase in GFR
Increased colloid osmotic pressure and decreased hydrostatic pressure of efferent arteriole increases tubular reabsorption of sodium and water

Question 4

Explain the effect of aldosterone on Potassium secretion

Answer 4

Aldosterone acts to up regulate basolateral NA+/K+ ATP pump resulting in more sodium retention and greater potassium secretion, 3 Na+ out 2K+ in maintains gradient

Question 5

What doe granular cells secrete

Answer 5

Renin

Question 6

Which part of the renal tubule is the macula densa

Answer 6

DCT

Question 7

How does the myogenic mechanism maintain filtration when BP is low

Answer 7

dilation of afferent arterioles