Session 4 - Part II

Question 1

What are the 4 long term reactions to Hypertension?

Answer 1

Renin Angiotensin Aldosterone System
Sympathetic Nervous System
Antidiuretic hormone
Atrial natriuretic peptide

Question 2

What are Granular cells?

Answer 2

In the Juxtaglomerular apparatus
Have beta adrenoreceptors
Release renin
Next to the Macula Densa of DCT
In the afferent arteriole

Question 3

What stimulates the granular cells to release renin?

Answer 3

Reduced NaCl delivery to the distal tubule

Decreased renal perfusion (sensed by baroreceptors)

Question 4

What does Renin do?

Answer 4

Convert Angiotensin I to Angiotensin II

Question 5

What are the 2 receptors of Angiotensin II?

Answer 5

AT1 & AT2 (GPCRs)

Question 6

What are the main actions of AT1?

Answer 6

Stimulate ADH

Interact with kidney, arterioles, SNS, Hypothalamus and adrenal cortex

Question 7

What are the main actions of AT2

Answer 7

Vasoconstriction of arterioles at glomerulus –> decreased blood flow and therefore decreased Na+ reabsorption

Question 8

What transporter is effected to have increased reabsorption of Na+ in the PCT?

Answer 8

NHX

Question 9

What receptor does Aldosterone act on?

Answer 9

Mineralocorticoid which increases gene transcription for Na+ channels (Blocked by spironolactone)

Question 10

What does Aldosterone act on?

Answer 10

Principle cells of collecting ducts. Increased reabsorption of ENaC and increased ATPase on the basolateral membrane

Question 11

What does ACE break Bradykinin down into?

Answer 11

Peptide fragments

Question 12

How does the Sympathetic nervous system effect Na+ transporters in the kidney?

Answer 12

Activates apical NCX
Basolateral Na/K ATPase in PCT
Stimulates renin release from Juxtaglomerular cells = Increased Na+ reabsorption