Renin Release	

Renin is released in repsonse to:
• Renal arteriolar blood pressure. 
• Changes in tubular sodium concentration.
• Stimulation via sympathetic nerves.
The major cause is a decrease in perfusion pressure, and this may result from haemorrhage, hypotension, or a reduction in the extracellular fluid volume after sodium depletion. 
Conversely, hyperkalaemia, angiotensin II, and antidiuretic hormone (ADH or vasopressin) can all inhibit renin secretion. 
The release of renin activates a cascade system. 

See also:
• Renal Hypertension