Renin-angiotensin system Flashcards
What type of receptors are AT1?
GPCR - G alpha q
Where is ACE produced?
Lungs on endothelial cells
Where is renin produced and released?
Kidneys - released from juxtaglomerular cells
Where is angiotensinogen produced?
Liver
What triggers aldosterone release?
Angiotensin II on adrenal cortex
What organ detects a decrease in blood volume and how?
Kidneys - glomerulus doesn’t filter as much, baroreceptors detect decrease in pressure, renin released.
What cells release renin?
Juxtaglomerular
Give 3 ways renin release can be stimulated
1) baroreceptors detecting decrease in volume in afferent arteriole
2) decrease of Na+ in distal convoluted tubule
3) sympathetic stimulation - NA
What can cause low blood volume?
1) Dehydration
2) Blood loss
What does the pituitary gland release?
ADH (anti-diuretic hormone)
How does aldosterone and ADH increase blood volume?
1) Increase Na+ channels
2) Increased Na+ reabsorbed
3) Osmosis = increase Na+ increases H2O
Blood volume increased
What pathway does G alpha q stimulate?
1) PLC phosphorylates PIP2 – > IP3 + DAG
2) IP3 –> increases Ca2+ release
3) forms calmodulin-calcium complex
4) MLCK phosphorylates myosin
5) Myosin binds to actin and causes smooth muscle contraction
6) VASOCONSTRICTION
increase peripheral resistance ect
