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Endocrine pancreas

The endocrine pancreas, a key player in diabetes, releases hormones that travel throughout the body. It houses alpha, beta, and delta islet cells, each with unique roles. Alpha cells release glucagon, which breaks down glycogen into glucose. Beta cells release insulin, which builds glucose into glycogen and is crucial in diabetes management. Delta cells release somatostatin, inhibiting other hormones. Understanding these functions is essential for tackling diabetes. Created by Raja Narayan.

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  • primosaur ultimate style avatar for user Skyler S
    Can a buildup of insulin from type 2 diabetes also be bad?
    (6 votes)
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  • female robot ada style avatar for user Ria Devani
    Why does sema tostatin cause the other hormones to be stopped and to no longer be active??
    (3 votes)
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  • blobby green style avatar for user Vantovant
    I have a friend who received a report that her heart has increased in size because of cysts that grew in the heart over time. Any idea what makes the cysts to develop in the heart.
    (2 votes)
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  • female robot amelia style avatar for user AndreMoezzi
    What the actual skdfjhasfhkj? I thought insulin breaks down sugar. Why does it say insulin builds up/stores sugar? Over weight people can break down insulin and that is why they take insulin shots so they can break down the sugars they have stored. Someone please straighten this out for me.
    (0 votes)
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    • leaf green style avatar for user Joanne
      We eat carbohydrates that we digest and absorb as glucose, a simple sugar and that raises our blood glucose levels. Insulin is a hormone or chemical made by the pancreas that is released into the blood and allows glucose to go INto the cells. When glucose goes into the cells, the amount in the blood decreases to a normal amount. Inside the cell, the glucose can be stored and later broken down to make energy. Diabetics have a problem with insulin, but they don't "break it down", you are incorrect. Because insulin is either not made (Type 1) or not able to be used (Type 2) the glucose can not get into the cells, so the cell can not make energy. Insulin is the key to the cellular lock that allows glucose in the door. Please watch the video again.
      (5 votes)
  • blobby green style avatar for user Fahreenzain996
    At Can low levels of somatostatin can cause hyperglycemia due to excess glucagon? As decreased amount of somatostatin leads to hypoglycemia due to excess insulin.
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  • blobby green style avatar for user bhavanirrr
    do pancreas also help with controlling norepinephrine and epinephrine from binding to beta receptors
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  • blobby green style avatar for user Adnan Faisal
    why does high blood glucose level stimulate somatostatin secretion? Cause somatostatin ends up inhibiting insulin secretion, but when blood glucose is high dont we need insulin to help the cells take in glucose?
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  • blobby green style avatar for user M E
    Isn't another function of the Beta-islet cells to alert cells within the body that they can absorb glucose in the blood to be used within the cell? Not just for the conversion of glucose into glycogen?
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  • duskpin ultimate style avatar for user alyssakowen
    If somatostatin causes the effects of the pancreatic hormones to stop, then why wouldn't it be a possible cause of diabetes? I understand that we see the pancreas not making insulin so we determine there is no insulin, but why couldn't it be that somatostatin is overproducing?
    (1 vote)
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  • female robot grace style avatar for user Anna
    Why doesn't he talk about something similar to diabetes caused by too much glucagon secreted by the pancreas even when the amount of insulin is in the normal range?
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    • piceratops ultimate style avatar for user Richard
      This is possible - a tumour of the pancreatic alpha cells (glucagonoma) can cause a person to secrete too much glucagon (leading to hyperglucagonemia), and this does produce high blood sugar like diabetes. However, it is much rarer than diabetes.
      (3 votes)

Video transcript

Alright, then on that note why don't we move onto the next part of the pancreas, which is known as the endocrine pancreas. And this is actually the part of the pancreas that is the most famous. We hear the most about this as we'll see in a minute because it has a lot to do with diabetes. The endocrine pancreas will release hormones rather than the salts or enzymes we saw above, "will release hormones" that go into the blood stream. And they will move on elsewhere throughout the body, to the liver perhaps the intestine, or even as far as muscles to cause things to happen. And the way the endocrine pancreas is organized is that there are many "eyes lit" cells, it's actually pronounced "eye-lets" but I'm mispronouncing it just to let you know how it's spelled. Islet cells that exist and sit in islands, "Sit in islands." So, there are three types, or three main types of islet cells that we're going to talk about and they're all present to some extent in each island, or group of cells in the pancreas. Let's go through them one by one. So, first of all, we've got what are called alpha islet cells, "alpha islet cells." And these guys release a hormone that's called glucagon, "glucagon". And the main function of glucagon is to take things like glycogen, which is a whole bunch of glucose molecules that are stacked up on top of each other, and then break them down into smaller glucose monomers or molecules. So, we're making glucose from glycogen whenever we release our glucagon. I'll write "glucagon" up here. And it's not just carbohydrates. But glucagon is responsible for the breakdown of a whole bunch of macromolecules. So, I'll just drive it home by writing, "glucagon causes break down" over here. The next type of islet cell that we have and perhaps the most famous of them all are our beta islet cells. So, our beta islet cells house and release insulin. Now when you hear "insulin", there should be a lot of lightbulbs coming up because insulin is responsible for a whole bunch of things. For one, when we look over here, insulin is what causes the opposite of this reaction, where instead of breaking down glucagen into glucose, insulin causes glucose to be stored or built up into glycogen. So insulin does the exact opposite. And again to drive that home. It's not just for carbohydrates, but its for a whole bunch of things that get built up. So I'll write "insulin is responsible for the build up or storage of our macromolecules". But what might be the most important thing to mention about insulin, is that it is the hormone that is related to or responsible for the disease known as diabetes. Gosh, we could have entire tutorials on diabetes and what it does and what it means. But for right now, just know that at it's bare basics, diabetes occurs or causes damage to our bodies because we have too much glucose, "too much glucose", floating around in our body, too much sugar, alright? And that happens because insulin is not working properly. We're not building up and storing glucose and glycogen like were supposed to be doing. Instead it's running all over the body. And because of that, we have what's called "eye, nerve and kidney disease", that's sort of the catch phrase we use in medicine to describe diabetes. It's eye nerve and kidney disease because with too much glucose over time we're unable to see. The nerves most commonly in our feet are not able to sense pricks or stings or damage that occurs there and eventually can cause amputation. And our kidneys stop working over time, which can lead to dialysis and that causes early death. And in addition to these three, glucose goes all over the body and causes a whole bunch of other things like earlier onset of heartattack and other types of complications. The other thing I should mention about diabetes is that there are two types of diabetes, "there are two types". There is type one diabetes and there is type two. And the way you differentiate type one versus Type two diabetes is based on how it's caused. And this all points back to insulin. In type one diabetes, we have no insulin. So, the person who has type one diabetes has no insulin production. And because of that we're not able to store our sugar and glycogen, we're not able to put it away. And so we have it all over the place. That causes eye nerve and kidney disease among other complications. In type two diabetes, your insulin receptors. So, you have insulin that's being produced, but your insulin receptors are broken, "your insulin receptors are broken". So, even if we do produce insulin and it goes where it's supposed to go in our body, these receptors will not respond. And so it's as if we don't have insulin in our body at all. And there's so much more that we can say here, but we'll close our conversation on diabetes for now and we'll revisit this later. Let's move on to the third type of islet cell we've got in the pancreas and those are delta islet cells, "delta islet cells". And these are the guys that release a hormone called "somatostatin" which is the major party pooping hormone released from the pancreas because its main job is to stop the jobs of all the other hormones that are active. And these hormones can include things like we've talked about here, glucagon, insulin. There are other hormones that are also contained in the GI tract that include things like cholecystokinin that we talked about elsewhere. And symatostatin will go in and cause the effects of those hormones to stop and that's sort of its main role there. So, that's our endocrine pancreas and we talked about earlier our exocrine pancreas. So, the pancreas is responsible for a lot. No wonder surgeons have the phrase, "Eat when you can, sleep when you can, and don't mess with the pancreas."