hi in this video I'm going to look at the renin Angiotensin Alder sterone system also known as the R so this all starts with the liver and the liver produces an pre- enzyme called Ang tensen and this gets converted into Angiotensin one and this occurs through the action of renin which is an enzyme released from the kidney and the kidney releases this due to low fluid volume moving through the ne now Angiotensin one gets converted to Angiotensin 2 and this happens by an enzyme called Angiotensin converting enzyme now these are floating around in the blood these Angiotensin so it's when they pass through the lungs that they meet Ace which lives in the lung and that's when Angiotensin one gets converted to Angiotensin 2 now Angiotensin 2 acts on the adrenal gland and it causes the adrenal gland to release alestone and that's a steroid hormone which then acts on the collecting ducts of the nefron this is within the the kidney and causes the nephron to retain water so I'll put here H2O retention then if the body retains water the blood pressure goes up and in some people this can be a bit of a problem now I should also put in one other thing that's very important about angot tensin 2 and otens 2 seems to be a factor in the inappropriate remodeling of a heart after a heart attack and this can cause significant morbidity and mortality in heart attack patients so let's have a look at some drugs which we can use to affect this pathway the most common drugs are the ACE inhibitors so these are the Angiotensin converting enzyme Inhibitors so obviously these inhibit Ace the next group of drugs are called stin or Angiotensin 2 receptor blockers also known as arbs and they stop the effects of angiotensin 2 and then a third set of drugs block the action of aldosterone and the most important of these is spironolactone it's also important to note that by blocking the action of angiotensin 2 the ACE inhibitors and the stin can prevent the remodeling of the heart after a heart attack so these drugs lead to a lower blood pressure and a better outcome after a heart attack and that's an overview of the Rin Angiotensin aldosterone for more free tutorials and the PDF for this tutorial visit www.h handwritten tutorial.com