Christina explains how the kidneys activate the RAA system when blood flow drops. Renin converts angiotensinogen to angiotensin II, which narrows blood vessels and triggers aldosterone release. Aldosterone makes the kidneys retain sodium and water, raising blood pressure and restoring renal blood flow.
Hey there, friend Christina here from nursingschoolofsuccess.com and in this video, today, we are diving into a really, really tricky nursing school topic, the renin angiotensin aldosterone system. This is one of those trickier nursing school topics, particularly because there are just so many moving parts. You've got renin, angiotensin, and aldosterone, and you've got to know everything that they do. So today we're gonna break it all down, really EAS you, so you can finally, finally understand the renin angiotensin aldosterone system for nursing school. We will also walk through some critical thinking points that you will want to know to bring it all together. And make sure to pin this video by clicking the share button down below and clicking the Pinterest icon. You can also head on over to our website and click the Pinterest button. Now, let's get to it. So this whole process starts when the kidneys are not getting enough blood flow. So it all starts with the kidneys. So here is what's going down. The kidneys get very, very unhappy when they don't get blood flow, right? So what do they do? They try their very, very best to increase blood flow to themselves. They want more blood, right? So they trigger something called the renin angiotensin aldosterone pathway, or the raa pat or the RAA system. Whatever you want to call it, it all means the same thing. So the first thing the kidneys do is release a hormone called renin. And renin stimulates the creation of angiotensin 1. So when the kidneys don't get enough blood flow, they release renin. And renin goes and helps to create angiotensin 1. And angiotensin I travels from the kidneys all the way up to the lungs, and it gets converted into angiotensin ii. So there are two angiotensins here, angiotensin I and angiotensin ii. So angiotensin I goes to the lungs and it gets converted to angiotensin ii. Cool. Cool. All right. Now, angiotensin II is very, very strong vasoconstrictor, meaning that it constricts the blood vessels. So angiotensin II makes the blood vessels more narrow, it constricts them. And angiotensin II also causes aldosterone to be secreted by the adrenal glands. So those are the two main jobs of angiotensin ii. It constricts the blood vessels and it causes aldosterone to be released. Now, let's talk about aldosterone. Aldosterone goes and tells the kidneys to hold onto as much water and as much salt as they can, and it tells it to get rid of potassium. So aldosterone is going to travel from the adrenal glands to the kidneys and tell the kidneys to hang onto water and hang on to salt and get rid of potassium into the urine. So that is what's going on. The kidneys aren't getting enough blood flow, so they release renin. Now, renin helps to create Angiotensin 1. And Angiotensin 1 then goes to the lungs and it's converted into angiotensin ii. Now, angiotensin II has two jobs. It constricts the blood vessels and it causes the release of aldosterone. Now, aldosterone then is going to go to the kidneys, and it's going to tell the kidneys to hold on to salt and hold onto water and get rid of potassium through the urine. So now that we know how this whole system works, let's walk through some critical thinking points. Now, what is the main purpose of this system? What are the kidneys trying to do here? Well, the renin, angiotensin, aldosterone system was triggered initially, remember, because the kidneys weren't getting enough blood. So all the kidneys want is more blood flow. They just need more blood to function. So the kidneys are really trying just to get more blood by stimulating this RAA system. So there are two key points in this system that help this all to happen. The first is angiotensin ii, and the second is aldosterone. So angiotensin II is, like we said, a vasoconstrictor. Right? You. So that means that it's going to cause the blood vessels to narrow. And when the blood vessels are more narrow, they're more constricted. It increases blood pressure and therefore will increase blood flow to the kidneys. See how that works? So that's all fine and dandy for the kidneys, right? Angiotensin II has constricted the blood vessels. The blood pressure now has increased, which means there can be more blood flow to the kidneys, which is what the kidneys bonded. Now, the second part of the RA system that leads to more blood flow to the kidneys is aldosterone release. Right? So aldosterone's job is to tell the kidneys to hold on to sodium and hold on to water and to get rid of potassium. So with the kidneys holding on to more water and holding on to more sodium, that means that fluid volume is going to go up in the body, meaning more blood. And when there's more blood flowing around the body, the kidney should get more blood. So that is how that works too. Aldosterone goes and tells the kidneys to hang on to salt and water, which increases the blood volume in the body and so the kidneys can get more blood. So they'd be pretty happy. And that is the renin angiotensin aldosterone system or the RAA system. And if you need more help in your med surg classes in nursing school, definitely check out all of the other videos that we have to help you out with. Med surg in nursing school school. Thank you so much for watching this video, friend. Now go become the nurse that God created only you to be and I will see you right back here next time on the Nursing school show. Take care of.
