Source: Images from Adobe Illustrator; Public Domain
Welcome to this lesson on pancreatic hormones. Today, we are going to be discussing the role of the various hormones associated with the pancreas. So the pancreas, its main role is to secrete hormones which help to regulate blood sugar levels. So it's secreting these hormones which help to adjust the level of blood sugar levels in order to help maintain homeostasis.
So we want to keep our blood sugar levels within a certain range. And the hormones that are secreted by the pancreas allow us to do this. So if we take a look at our picture down here, this organ here is the pancreas. So pancreatic islets are groups of three types of cells in the pancreas that secrete hormones. So those groups of three types of cells are alpha cells, beta cells, and delta cells. So these are the three types of cells found in those pancreatic islets.
And each of these three types of cells secretes a different hormone that has a different role in regulating blood sugar levels. So alpha cells, for example, secrete glucagon. And glucagon is a hormone which helps to increase blood sugar levels.
So let's say that you've had a super-busy day. You haven't had breakfast, you missed lunch. It's getting later in the day, and you still haven't eaten anything. At this point, what's going to happen is that your blood sugar levels will start to drop because you haven't eaten anything. So those alpha cells in the pancreas will then secrete glucagon. And that glucagon will help to raise those blood sugar levels to bring them back to a homeostatic point. So it's helping to raise the blood sugar levels if they get too low.
Beta cells are a type of cell found in these pancreatic islets that secrete insulin. So insulin is a hormone that maybe you're a little bit more familiar with. And insulin helps to decrease blood sugar levels. So if blood sugar levels start to get too high, insulin is responsible for lowering them.
So it's getting pretty close to Halloween right about now. Let's say that you take your little brother or sister or your own kid out trick-or-treating. And they fall asleep, and you decide to go through their candy bag and binge on a bunch of their candy. Your blood sugar levels at that point are just going to skyrocket. So beta cells will secrete insulin, which helps to lower those blood sugar levels to help maintain that homeostatic point.
Somebody who is diabetic, however, their beta cells-- it's an autoimmune disease. So their beta cells are not properly functioning, so they're not able to secrete this insulin. So instead, since their body doesn't secrete insulin, they have to take insulin injections in order to lower their blood sugar levels. OK.
And then delta cells secrete somatostatin. And somatostatin is a hormone that helps to regulate the functioning of these alpha and beta cells. So alpha, beta, and delta cells are the three types of cells that are found in pancreatic islets that help to regulate these blood sugar levels. So this lesson has been an overview on the role of pancreatic hormones.
Islets of cells on the pancreas containing cells that manufacture the hormones insulin and glucagon along with many exocrine secretions for the digestive system; also referred to as the islets of Langerhans.
Cells of the pancreas that secrete glucagon.
A hormone released by alpha cells in the pancreas which raises blood sugar levels.
Cells of the pancreas which secrete insulin.
A hormone released by beta cells in the pancreas which lowers blood sugar levels.
Cells of the pancreas which secrete somatostatin.
The exact function of this hormone is not well understood but it’s believed that it may help regulate alpha and beta cell activity along with some digestive functions.