Final answer:
The three triggers that release renin from the juxtaglomerular complex are decreased extracellular fluid volume, sympathetic nervous activity, and the release of prostaglandins and NO from the JGC.
Step-by-step explanation:
The juxtaglomerular complex (JGC) releases renin in response to various triggers. These triggers include decreased extracellular fluid volume, sympathetic nervous activity, and the release of prostaglandins and NO from the JGC.
When the extracellular fluid volume decreases, the JGC detects this and stimulates the release of renin. This enzyme is produced by the granular cells of the afferent arteriole at the JGC. Renin then acts on angiotensinogen, which is made in the liver, converting it into angiotensin I. Angiotensin I is then converted into angiotensin II, which regulates blood pressure and volume by stimulating the release of aldosterone and ADH.
In summary, the three triggers that can lead to the release of renin by the juxtaglomerular complex are decreased extracellular fluid volume, sympathetic nervous activity, and the release of prostaglandins and NO from the JGC.