RAAS system Flashcards
1
Q
Responsible for Renin production/release
A
Juxtaglomerular cells in KIDNEY
2
Q
Production of Angiotensinogen
A
Liver
3
Q
Role of ACE
A
converts AngI to AngII
4
Q
Baroreceptor mechanism
A
- decreased pressure in afferent arteriole=renin release
- increased pressure in afferent arteriole= stop renin release
5
Q
Sympathetic Nerve mechanism
A
B1 adrenergic nerves stimulate renin release
- “fight or flight” to increase BP
6
Q
Macula Densa mechanism
A
- chemoreceptors in distal convoluted tubule that detect how much NaCl passes through
- Decreased NaCl=promotes renin release
- Increased NaCl= stops renin release
7
Q
goal of renin
A
increase BP
8
Q
Effects of AngII on smooth muscle
A
- vasoconstriction
- increased resistance
- RAPID
9
Q
effects of AngII on kidney reabsorption
A
- will promote Na reabsorption
- H2O retention follows
- increased arteriole pressure
- increased stroke volume
- SLOW
10
Q
Effects of AngII on pituitary gland
A
- the pituitary gland will release ADH (anti-diuretic hormone)
- causing H2O retention
- arteriole pressure goes up
11
Q
Effects of AngII on adrenal gland
A
- stimulates the adrenal gland to release aldosterone
- Na reabsorption
- H2O reabsorption
- increased arteriole pressure
- increased stroke volume
12
Q
AT1 receptor
A
- GPCR
- mediates hypertensive, renal, and hypertrophic (enlargement) effects of AngII
- structurally flexible
13
Q
AT2 receptor
A
- counteracts many effects of AT1
- vasodilation, antiproliferative, anti-inflammatory, antihypertensive effects
- can bind and inhibit AT1
- widely found in fetal tissues
14
Q
Renin Short-loop negative feedback
A
- increased renin release
- increased AngII production
- stimulation of AT1 receptors on JG cells to inhibit renin release
15
Q
Renin Long-loop negative feedback
A
- AngII increases arterial BP via AT1 receptors
- inhibits renin release by:
1) activating high-pressure baroreceptors to reduce renal synaptic tone
2) increasing pressure in preglomerular vessels
3) reducing NaCl reabsorption in proximal tubule leading to greater tubular delivery of NaCl to the macula densa which inhibits renin release (macula densa mechanism)
