The pancreas is a gland organ that can be located in the abdomen behind the stomach. It is a dual functioning organ that is part of both the digestive and endocrine systems. The digestive system is responsible for the breakdown of food into usable vitamins, minerals, nutrients and energy. The endocrine system releases various hormones into the body to regulate mood, growth and development, tissue function and metabolism.
What does the pancreas do as part of the digestive system?
The pancreas is an important part of the body’s digestive system as it secretes pancreatic juices into the small intestine. These juices flow through a duct connected to the duodenum called the pancreatic duct. Pancreatic juices contain digestive enzymes that break down carbohydrates, proteins and fats in the chyme. Chyme is partly digested food that is passed from the stomach to the small intestine. Some of the enzymes that can be found in the pancreatic juices are trypsin, chymotrypsin, carboxypeptidase, lipase and amylase. Both trypsin, chymotrypsin breakdown the protein in the chyme. Lipase is responsible for breaking down fat and amylase breaks down starch or carbohydrates. The pancreas also secretes another substance that helps to neutralize the stomach acid.
The flow of the digestive system is often altered during the surgical treatment of pancreatic cancer. Therefore it is helpful to review the normal flow of food before reading about surgical treatment.
Food is carried from the mouth to the stomach by the esophagus. This tube descends from the mouth and through an opening in the diaphragm. (The diaphragm is a dome shaped muscle that separates the lungs and heart from the abdomen and assists in breathing.)
Immediately after passing through the diaphragm's opening, the esophagus empties into the stomach where acids that break down the food are produced. From the stomach, the food flows directly into the first part of the small intestine, called the duodenum. It is here in the duodenum that bile and pancreatic fluids enter the digestive system.
What does the pancreas do as part of the endocrine system?
As part of the endocrine system the pancreas produces several different hormones. The four hormones it produces are called insulin, glucagon somatostatin and pancreatic polypeptide. Insulin is the hormone responsible for decreasing the glucose level (sugars) in your blood. It does this by increasing the rate at which your cells can absorb glucose. When too much glucose is present insulin causes the body to store the excess amount as glycogen in the liver. Glucagon is the hormone the body secretes to increase the level of glucose (sugars) in the blood. The pancreas will release this hormone when the level of glucose (sugars) in the blood falls too low. This triggers the body to convert some of the glycogen stored in the liver back into glucose of the body to use. Without sufficient amounts of glucose the body cannot function correctly as the absorption of glucose releases energy. Somatostatin regulates the production of both hormones insulin and glucagon within the pancreas. The function of pancreatic polypeptide is largely unknown but is thought to help with the regulation of pancreatic secretions. Somatostatin is able to regulate the level of pancreatic polypeptide released by the pancreas.
What are the functions of Insulin?
Insulin is essential for life. It reduces blood sugar by stimulating sugar uptake by the cells. It also stimulates amino acid entrance into the cells. It stimulates the formation of gycogen which is the chief storage form of carbohydrates, stored mainly in the liver, muscles, & fat cells. Insulin promotes the synthesis of proteins & promotes growth. It regulates fat metabolism, increases fat formation, maintains fat stores, & inhibits the mobilization of fat from peripheral stores.
Insufficient insulin results in insulin dependent diabetes. Excess insulin can cause the cells to become less sensitive to the insulin & result in adult onset insulin resistant diabetes which is controlled with diet & medications other than insulin. Excess insulin with insulin administration or with insulin resistance can contribute to obesity, high blood pressure, high blood fats & atherosclerotic heart disease.
Insulin release is stimulated by foods, other GI tract hormones, stress hormones, & acetylcholine. Calcium is an important mediator of insulin activity & activates the glucose transport system in the cells. A calcium deficiency will compromise some of the actions of insulin.
What are the functions of Glucagon?
Glucagon is not essential to life. It works antagonistically to insulin, by increasing rather than decreasing blood sugar. It acts as a fuel mobilizer by stimulating glycogen (stored carbohydrate) release from the liver & muscles. It also promotes the formation of glucose from amino acids (protein) when that is needed. Its’ release is stimulated by hypoglycemia & fasting. It stimulates fat metabolism helping to break down fat & promotes the repair of injured tissues. It increases blood potassium, increases oxygen consumption & promotes sodium excretion.
Proteins & amino acids, gastrointestinal hormones, prolonged exercise, stress hormones, & acetylcholine also stimulate its’ release.
Proteins & amino acids, gastrointestinal hormones, prolonged exercise, stress hormones, & acetylcholine also stimulate its’ release.
Sugar, fatty acids, & hormones suppress its’ release.
Hypoglycemia is a stress state stimulating the output of Glucagon & other hormones to mobilize fuel from the liver & muscles. But this regulatory response to hypoglycemia is impaired in many older people who have impaired ability to maintain glucose balance. Influences are diet, exercise, nutritional status, body fat per cent, hormone levels, medications, & disease.
Common Diseases
Diseases associated with the pancreas include diabetes, pancreatic cancer, pancreatitis, and cystic fibrosis, among many others. Any interference with our insulin or enzyme levels wreaks havoc on our well being, whether it is due to genes or diet.
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