Video: Renal arteries

Hello, everyone! This is Joao from Kenhub, and welcome to another anatomy tutorial where, this time, I’m going to be talking about the renal arteries – these blood vessels that supply two organs in your body: the kidneys, as you can now see on the image.

We are looking at the anterior view of the abdomen if we were to strip all the organs that you can find on a more anterior side of… or ventral side of the abdomen, and we’re left with, then, the kidneys. They are found a bit more posteriorly because the kidneys are retroperitoneal organs and their main function is to, then, eliminate excess bodily fluid, salts, and byproducts of protein metabolism.

And as you can see, they have this bean-shaped… they are what we also call bean-shaped organs which receive blood supply from, then, the renal arteries, which are the topic of this tutorial. And these arteries are branches of this main artery here, this blood vessel (very important) in your body, the aorta, or we can call it, in this region of your body, you can call it the abdominal aorta.

And you can also see here the vessels that we’re going to be talking about, the renal arteries, which will, then, supply the kidneys with blood.

Now, we’re going to move on and talk about the topic of this tutorial, where you now see a section of the kidney, we’re cutting it in half and exposing here the blood vessels that we’re going to be discussing on this tutorial. So now, you’re seeing the renal arterial supply, and we’re going to start off with this one that you see now, highlighted in green. This is the main renal artery. So we call it the right renal artery, but you also have another one that is important for the left kidney, which is the left renal artery.

But what I’m going to be doing is, since we’re looking right now at the right kidney, it makes sense to call it by its right name, its correct name, but keep in mind that the information that I’m going to be providing you will serve for both of these arteries – the right one and the left one.

Now, the renal arteries will arise from the abdominal aorta at the level of L1 and L2, the first and second lumbar vertebrae. This is due to the asymmetrical position of the left and right kidneys. So, as you probably remember, the right kidney is slightly lower than the left one.

Also important to know that the renal arteries will give off two main branches as it enters the hilum of the kidneys, this area right about here. And these branches are known as the anterior branch that you see here and the posterior branch that you can see going a little bit further behind, and this is the posterior branch.

But we’re going to look at them in a little bit more detail later on on this tutorial.

I would still like to make a point here about the renal arteries, and as you can see here now, on this image, we’re looking at… this is the right kidney and the left kidney. Keep in mind that we’re looking at the subject’s perspective. And notice here that the right renal artery is entering the hilum of the right kidney behind or posterior to this big blood vessel here, known as the inferior vena cava.

While on the other hand, you have here the left kidney and the left renal artery going now or entering the hilum of the left kidney, but now, behind this blood vessel here, which is known as the left renal vein.

The next branch that we’re going to be talking about is known as… and seen now, highlighted in green, this is known as the inferior suprarenal artery, and the inferior suprarenal artery is the first branch of the renal artery that supplies the suprarenal gland. It arises from the renal artery before the terminal branches.

We’re going to move on to this one that you see, highlighted in green, that I briefly mentioned on a previous slide. This one is known as the anterior branch of the renal artery, also known as the anterior ramus.

And this one, this branch, will give off four segmental branches or segmental arteries that we will be discussing on this tutorial. One is the superior segmental artery. The other one is the anterior superior segmental artery, also the anterior inferior segmental artery, and the inferior segmental artery—all of these that will be covered here.

Now, the next one, let’s start off, then, the next slide that will cover one of these segments known as the superior segmental artery. And the superior segmental artery is the first segmental branch, if you remember correctly, from that list that I just mentioned, of the anterior branch of the renal artery.

This artery, as the name suggests, it will supply the superior segment of the kidney.

We’re going to move on and talk about another of these branches that we saw on that list. This one is the anterior superior segmental artery which supplies the anterior superior segment of the kidneys. So it’s very easy to remember this. As long as you know the name, then you can predict what supply is associated to this particular branch.

Now, the anterior superior segmental artery is the second segmental branch of the anterior branch of the renal artery, as we saw on that previous list.

Now, we’re ready to move on to another branch seen here, highlighted in green. This is known as the anterior inferior segmental artery, which is situated inferior to the anterior superior segmental artery. Wow, long names.

Now, this will supply the anterior inferior segment of your kidneys and is, then, the third segmental artery of the anterior branch of the renal artery, as we saw also on that previous list.

We’re going to move on to the last one on the list. This one is the inferior segmental artery. And this is, then, the final segment of the anterior branch of the renal artery and is the inferior segmental artery, as you can see here.

Now, the inferior segmental artery supplies the lower portion or inferior segment of the kidneys.

Now that we covered all the branches of the anterior branch of the renal artery, it is time for us to move on to, then, now, as you can see here, highlighted in green, if you remember correctly, this is now the posterior branch of the renal artery. And the posterior branch or posterior ramus of the renal artery gives rise to only one segmental artery, which is, then, known as the posterior segmental artery.

Now, I have already given you a hint on the next one that we’re going to be talking about. These are the posterior segmental arteries, seen here, highlighted in green.

Now, the posterior segmental arteries are the only segments arising from the posterior branch of the renal artery, and these segmental branches supply the posterior segment of the kidneys.

The next ones that we’re going to be talking about are now seen, highlighted on the screen, in green, and these are the interlobar arteries of the kidney.

Now, these interlobar arteries arise from the segmental arteries of the kidney, as you can clearly see on this image. And these arteries are located between the—of course, as the name indicates as well—the renal lobes, which are basically the medullary pyramids and also the renal cortex. So keep that in mind.

“Interlobar” means they are between the lobes. They’re going to, then, be supplying these areas of the kidneys.

There are also another set of arteries that are known as the interlobular arteries of the kidney. They have a similar name, but the interlobular arteries arise from these ones that you see here, the arcuate arteries, that we’re also going to be covering here on this tutorial.

And these interlobular arteries also supply the renal cortex and are terminal ends.

As I mentioned before, the next ones are known as the arcuate arteries. The arcuate arteries are seen here, located at the corticomedullary border, meaning the border between the renal cortex and the medulla.

Now, the terminal arteries are formed, then, by the interlobular arteries, and they arise from these arcuate arteries.

Next in line is this one that you see, highlighted in green. This is known as the branch of the renal pelvis. If you remember well from our tutorial that we talked about the structure of the kidney, yes, this is the renal pelvis. And for that reason, there is this branch that is going to be supplying this area of the kidney.

Now, the branch of the renal pelvis arises from the renal artery. And as I mentioned, this supplies the renal pelvis. There are several variations of how this artery arises to supply the renal pelvis, but for now, I just wanted to give you an idea of the supply associated to this artery and also the location and where it branches off from.

Now, the last one on this tutorial is going to be, then, this, seen here, highlighted in green, known as the ureteric branch of the renal artery. And as you can see here, if you remember from our previous tutorials, this is the ureter that is now connected to the renal pelvis, and then goes all the way to meet with the urinary bladder.

And you can see this branch here that is supplying the portion of the ureter that is closer to the renal pelvis.

And this branch also gives off several small branches to the ureter.