There’s a movie called “Space Cowboys” … and when one of the characters is told he has terminal cancer in his pancreas, he asks, “What is a pancreas anyway?” I find a lot of people do not know what or where their pancreas is, or what it does. Those that know something will query, “It has something to do with insulin, right?” As a matter of fact, that’s right. This month I’d like to offer you a brief introduction to the pancreas.
To begin, I need to provide you with a clear understanding of what enzymes are. There are numerous chemical reactions in the body that would happen slowly, if not for a specific enzyme that intervenes and speeds up that chemical reaction. In this regard, the enzyme is a catalyst. Certain laundry detergents sometimes advertise that they contain enzymes that break up food stains.
What does the pancreas look like? Unlike a kidney, the pancreas looks more like a sponge. It blends in with surrounding soft tissue. The shape of a tad pole is often used to describe it, but the surface of it is more globular. The reason for that might be that is secretes hormones as well as digestive enzymes. The main hormone is insulin. The digestive enzymes are proteolytic enzymes, pancreatic amylase and pancreatic lipase. More about them later.
Where does the pancreas reside? This elongated gland is located behind the stomach, just above the small intestine. The large end is snug up against the liver on the right, just under the right rib cage. The tail end stretches across the body sometimes clear to the other side. Within the pancreas are two main ‘factory type’ issues. One set of ‘factories’ are the insulin producers called the islets of Langerhans, and they secrete the Insulin to the blood. The digestive enzymes come from grape-like clusters of secretory cells that form sacs, known as acini. These sacs are connected together with ducts that eventually go to the small intestine along with bile from the gallbladder, using a tube called “the common bile duct”. The two different functions
in the same gland do not interact and it is said they have nothing in common except for sharing the same location. My theory is that they are very connected by the nervous system to do the task of digesting food and regulating blood levels of pH, blood sugar, and other interdependent body processes.
Proteolytic enzymes are involved in protein digestion. There are three major types: trypsinogen, chymotrypsinogen and procarboxypeptidase. These are held in an inactive form, so they do not ‘digest’ pancreatic tissue. Enterokinase is an enzyme secreted from cells that line the beginning of the small intestine. Their job is to activate the trypsinogen, which is then renamed trypsin. Trypsin autocatalytically activates more trypsinogen. Trypsin also converts chymotrypsinogen and procarboxypeptidase to their active forms, chymotrypsin and carboxypeptidase, respectively, in the first part of the small intestine. The goal of these is to break up the different peptide linkages of the proteins to get a mixture of amino acids and small peptide chains. Mucus is also secreted by the intestinal cells in order to protect against digestion of the walls of the small intestine.
Pancreatic amylase works along with salivary amylase to digest carbohydrates, there is no need to activate it. There is no danger to the secretory cells being in contact with active amylase. Pancreatic lipase is the only enzyme throughout the entire digestive system that can accomplish digestion of fat. It hydrolyzes dietary triglycerides into monoglycerides and free fatty acids which can then be absorbed into the body.
In addition to these enzymes, the acinar cells also produce a potent enzymatic secretion and a watery alkaline secretion rich in sodium bicarbonate (NaHCO3). Pancreatic enzymes function best in a neutral or slightly alkaline environment. Thus, the extremely acidic stomach contents must be neutralized quickly for this reason, and to protect the lining of the small intestine. That is the main function of this watery alkaline secretion. The volume
of pancreatic secretion ranges between 1 to 2 liters per day. Those are main points for the pancreas as to digestion. There are other amazing details that deal with a fine balance of acid and base chemical reactions. The system has feedback loops to either stimulate or inhibit secretions of several other digestive phases.
Before I talk about insulin, I want to distinguish hormones from other substances in the body. Hormones are long-range chemical mediators, specifically secreted into the blood by ductless glands. The blood carries them to other sites in the body and the effects of the hormone can be some distance away from the site of its release. A single hormone may be secreted by more than one endocrine gland. Cells that are meant to receive a certain hormone will have special openings, like gates that allow the hormone into the cell.
Insulin has several jobs. The one I want to discuss today is the job of regulating blood sugar levels. Here’s a simple explanation. In the mouth there are sensors that tell the brain you have consumed something with a lot of sugar. When the brain perceives that blood sugar is high, it will cause the pancreas to secrete more insulin. Insulin floats in the blood and grabs the ‘sugar’ molecule and takes it to a cell. It doesn’t enter the cell; it opens the gate to push the sugar into the cell and thus lowers the blood sugar level. What could go wrong? Lots of things.
The cells have to have the right number of ‘gates’ for the insulin to do its job well. If the cell has enough sugar already it has ways to keep its gates shut. Also, if a person ingests sugar too often the gates can get damaged and they stop being able to receive sugar even if the cell needs it. This makes the job of the insulin much harder. This is a simplified explanation for a condition called “insulin resistance”.
To explain insulin deficiency, I offer some ideas. Perhaps genetically, a person has a very small pancreas. That might limit the number of islets of Langerhans, so insulin production might be diminished. There may also be other reasons the pancreas may not
have enough islets of Langerhans and has trouble making enough Insulin in the first place. Also, consuming too much sugar, which increases the body’s need for insulin can ‘burn out’ the ability of the little islets of Langerhans to keep making Insulin. It has long been noticed that diabetes has a tendency to occur in families. This might be one explanation of that.
While I’m on the topic of hormones (even though it has nothing to do with the pancreas), let me mention growth hormone. Science books refer to it as growth and repair hormone. When you are still growing, this hormone is responsible for helping the natural growth processes occur. To get energy into the cells, this hormone has a very similar capacity to take blood sugar and push it into cells. When we stop growing this same hormone still has the function of getting energy into cells that have been damaged or need repair for some other reason. Exercise has the potential to promote this situation. When a person exercises, the body has some wear and tear and will need that growth hormone to help the process. Growth hormone is usually released into the system while we sleep, that is one of the reasons children need lots of rest to grow properly. Diabetics have told me they feel a drop in their blood sugar about the time they are needing to wake up for the day. They report this phenomenon was explained to them to help them manage their diabetic needs. So, there you have a simplified, but solid description and explanation of your pancreas.
To begin, I need to provide you with a clear understanding of what enzymes are. There are numerous chemical reactions in the body that would happen slowly, if not for a specific enzyme that intervenes and speeds up that chemical reaction. In this regard, the enzyme is a catalyst. Certain laundry detergents sometimes advertise that they contain enzymes that break up food stains.
What does the pancreas look like? Unlike a kidney, the pancreas looks more like a sponge. It blends in with surrounding soft tissue. The shape of a tad pole is often used to describe it, but the surface of it is more globular. The reason for that might be that is secretes hormones as well as digestive enzymes. The main hormone is insulin. The digestive enzymes are proteolytic enzymes, pancreatic amylase and pancreatic lipase. More about them later.
Where does the pancreas reside? This elongated gland is located behind the stomach, just above the small intestine. The large end is snug up against the liver on the right, just under the right rib cage. The tail end stretches across the body sometimes clear to the other side. Within the pancreas are two main ‘factory type’ issues. One set of ‘factories’ are the insulin producers called the islets of Langerhans, and they secrete the Insulin to the blood. The digestive enzymes come from grape-like clusters of secretory cells that form sacs, known as acini. These sacs are connected together with ducts that eventually go to the small intestine along with bile from the gallbladder, using a tube called “the common bile duct”. The two different functions
in the same gland do not interact and it is said they have nothing in common except for sharing the same location. My theory is that they are very connected by the nervous system to do the task of digesting food and regulating blood levels of pH, blood sugar, and other interdependent body processes.
Proteolytic enzymes are involved in protein digestion. There are three major types: trypsinogen, chymotrypsinogen and procarboxypeptidase. These are held in an inactive form, so they do not ‘digest’ pancreatic tissue. Enterokinase is an enzyme secreted from cells that line the beginning of the small intestine. Their job is to activate the trypsinogen, which is then renamed trypsin. Trypsin autocatalytically activates more trypsinogen. Trypsin also converts chymotrypsinogen and procarboxypeptidase to their active forms, chymotrypsin and carboxypeptidase, respectively, in the first part of the small intestine. The goal of these is to break up the different peptide linkages of the proteins to get a mixture of amino acids and small peptide chains. Mucus is also secreted by the intestinal cells in order to protect against digestion of the walls of the small intestine.
Pancreatic amylase works along with salivary amylase to digest carbohydrates, there is no need to activate it. There is no danger to the secretory cells being in contact with active amylase. Pancreatic lipase is the only enzyme throughout the entire digestive system that can accomplish digestion of fat. It hydrolyzes dietary triglycerides into monoglycerides and free fatty acids which can then be absorbed into the body.
In addition to these enzymes, the acinar cells also produce a potent enzymatic secretion and a watery alkaline secretion rich in sodium bicarbonate (NaHCO3). Pancreatic enzymes function best in a neutral or slightly alkaline environment. Thus, the extremely acidic stomach contents must be neutralized quickly for this reason, and to protect the lining of the small intestine. That is the main function of this watery alkaline secretion. The volume
of pancreatic secretion ranges between 1 to 2 liters per day. Those are main points for the pancreas as to digestion. There are other amazing details that deal with a fine balance of acid and base chemical reactions. The system has feedback loops to either stimulate or inhibit secretions of several other digestive phases.
Before I talk about insulin, I want to distinguish hormones from other substances in the body. Hormones are long-range chemical mediators, specifically secreted into the blood by ductless glands. The blood carries them to other sites in the body and the effects of the hormone can be some distance away from the site of its release. A single hormone may be secreted by more than one endocrine gland. Cells that are meant to receive a certain hormone will have special openings, like gates that allow the hormone into the cell.
Insulin has several jobs. The one I want to discuss today is the job of regulating blood sugar levels. Here’s a simple explanation. In the mouth there are sensors that tell the brain you have consumed something with a lot of sugar. When the brain perceives that blood sugar is high, it will cause the pancreas to secrete more insulin. Insulin floats in the blood and grabs the ‘sugar’ molecule and takes it to a cell. It doesn’t enter the cell; it opens the gate to push the sugar into the cell and thus lowers the blood sugar level. What could go wrong? Lots of things.
The cells have to have the right number of ‘gates’ for the insulin to do its job well. If the cell has enough sugar already it has ways to keep its gates shut. Also, if a person ingests sugar too often the gates can get damaged and they stop being able to receive sugar even if the cell needs it. This makes the job of the insulin much harder. This is a simplified explanation for a condition called “insulin resistance”.
To explain insulin deficiency, I offer some ideas. Perhaps genetically, a person has a very small pancreas. That might limit the number of islets of Langerhans, so insulin production might be diminished. There may also be other reasons the pancreas may not
have enough islets of Langerhans and has trouble making enough Insulin in the first place. Also, consuming too much sugar, which increases the body’s need for insulin can ‘burn out’ the ability of the little islets of Langerhans to keep making Insulin. It has long been noticed that diabetes has a tendency to occur in families. This might be one explanation of that.
While I’m on the topic of hormones (even though it has nothing to do with the pancreas), let me mention growth hormone. Science books refer to it as growth and repair hormone. When you are still growing, this hormone is responsible for helping the natural growth processes occur. To get energy into the cells, this hormone has a very similar capacity to take blood sugar and push it into cells. When we stop growing this same hormone still has the function of getting energy into cells that have been damaged or need repair for some other reason. Exercise has the potential to promote this situation. When a person exercises, the body has some wear and tear and will need that growth hormone to help the process. Growth hormone is usually released into the system while we sleep, that is one of the reasons children need lots of rest to grow properly. Diabetics have told me they feel a drop in their blood sugar about the time they are needing to wake up for the day. They report this phenomenon was explained to them to help them manage their diabetic needs. So, there you have a simplified, but solid description and explanation of your pancreas.
