Angiotensin II
The key hormone for Na homeostasis!
| Net effect: | raises blood pressure, causes Na and water retention |
|---|---|
| Secreted from | Angiotensinogen → Angiotensin I → cleaved by ACE, see Renin-angiotensin-aldosterone system |
| Stimulus | |
| Inhibition | |
| Site of action | Proximal tubule, glomerular afferent arterioles |
| Time course of action | inactivated rapidly (within 1-2 mins) by angiontensinases in blood/tissue |
| Action (function) | - systemic vasoconstriction - vasoconstriction of glomerular afferent arterioles - stimulates Na reabsorption via action on Na-H antiporter in proximal convoluted tubule - ↑ aldosterone secretion, NO release - stimulates thirst - potentiates sympathetic activity - inhibits renin |