Ampulla of Vater

The ampulla of vater is the duodenal end of the drainage systems of the pancreatic and common bile ducts

Bile Duct

Within the liver lobules, there are many fine "bile canals" that receive secretions from the hepatic cells. The canals of neighboring lobules unite to form larger ducts, and these converge to become the "hepatic ducts." They merge, in turn, to form the "common hepatic duct." The "common bile duct" is formed by the union of the common hepatic and the cystic ducts. It leads to the duodenum, where its exit is guarded by a sphincter muscle. This sphincter normally remains contracted until the bile is needed, so that bile collects in the common bile duct and backs up to the cystic duct. When this happens, the bile flows into the gallbladder and is stored there.

Duodenum

The duodenum, which is the first portion of the small intestine, is about 25 cm long and 5 cm in diameter, is the most fixed portion of the small intestine. It follows a C-shaped path as it passes in front of the kidney and the upper three lumbar vertebrae. At its end, it joins the jejunum - the second portion of this intestine.

Esophagus

The esophagus is a muscular tube which carries food and liquids from the throat to the stomach for digestion after it has been chewed and chemically softened in the mouth. Food is forced downward to the stomach (or upwards, if one is standing on his head) by powerful waves of muscle contractions passing through the walls of the esophagus. Because these contractions are so strong in the throat and the esophagus, we can swallow in any position -- even upside-down! If the food is bad, poison, or more than we can "stomach," it may travel back by the same force to be thrown out through the mouth, which is called vomiting. The esophagus has a ring of muscle at the top and at the bottom. These rings close or contract after the food passes through and enters the stomach, where there is an abundance of churning acid waiting to digest the food. If the bottom muscle weakens, stomach contents, along with the stomach acid, may return to the esophagus and cause an uncomfortable, burning sensation known as "heartburn", although it is not connected with the heart at all, but be careful next time you are forced to swallow your pride.

Gallbladder

The gallbladder is an active storage shed, which absorbs mineral salts and water received from the liver and converts it into a thick, mucus substance called "bile," to be released when food is present in the stomach. The gallbladder is a small, pear-shaped sac which is situated just below the liver and is attached to it by tissues. It stores bile and then releases it when food passes from the stomach to the duodenum (the first part of the small intestine) to help in the process of digestion. It has a capacity of around one and one-half fluid ounces. When food leaves the stomach, a secretion causes the gallbladder to contract and expel its contents into the duodenum, where the bile disperses the fats in the food into liquid. Pythagoras, the 6th Century BC Greek mathematician, believed that life is based on the four elements of earth, air, fire and water which correspond to the body's "humors": blood (hot and moist), phlegm (cold and moist), yellow bile (hot and dry) and black bile (cold and dry). The perfect or imperfect balance of these humors supposedly determined one's health and intelligence. We still speak in terms of "melancholia" (excess black bile, leading to depression) and "phlegmatic" (sluggish or impassive) and scientists have named the heavy mucus secreted in the respiratory passages - phlegm. Pythagoras was kind of a "square". Oh, come on; where's your sense of "humor"?

Stomach

A hollow, sac-like organ connected to the esophagus and the duodenum (the first part of the small intestine), the stomach consists of layers of muscle and nerves that continue the breakdown of food which begins in the mouth. The gastric canal is formed by longitudinal ridges found on the interior of the lesser curve of the stomach. It has several other names, including "magenstrasse," "ventricularis," "ventricular canal," and "canal of stomach." Gastric folds are found on the interior of the stomach. Occasionally, with some diseases gastric folds become enlarged, thus providing indicators for disease. The stomach is also a storage compartment, which enables us to eat only two or three meals a day. If this weren't possible, we would have to eat about every twenty minutes. The average adult stomach stretches to hold from two to three pints and produces approximately the same amount of gastric juices every twenty-four hours. The stomach has several functions: (1) as a storage bin, holding a meal in the upper portion and releasing it a little at a time into the lower portion for processing; (2) as a food mixer, the strong muscles contract and mash the food into a sticky, slushy mass; (3) as a sterilizing system, where the cells in the stomach produce an acid which kills germs in "bad" food; (4) as a digestive tub, the stomach produces digestive fluid which splits and cracks the chemicals in food to be distributed as fuel for the body. The process of digestion is triggered by the sight, smell or taste of food, so that the stomach is prepared when the food arrives. Every time you pass a bakery shop or smell your mother's good cooking, the body begins a digestive process. If the stomach is not filled, these gastric juices begin eroding the stomach lining itself, so fill 'er up!

Pancreas

The pancreas is a long. tapered gland which lies across and behind the stomach. The "head" (the right-hand end which is the broadest part of it) lies within the curve of the duodenum. This gland secretes digestive juices which break down fats, carbohydrates, proteins and acids; it also secretes bicarbonate, which neutralizes stomach acid as it enters the duodenum. Some cells in the pancreas secrete hormones which regulate the level of glucose in the blood. Most of the pancreas consists of tissues which are embedded in "nested" cells. These cells secrete the digestive enzymes into tubes which meet to form the main duct. This duct joins the "cystic" duct (which carries bile from the gallbladder) and forms a small chamber which opens into the duodenum. The cells of the pancreas are surrounded by many blood vessels into which they secrete hormones (glucagon and insulin) into the blood. Insulin regulates the use of glucose into all the body tissues except the brain. If the pancreas fails to produce insulin or secretes it in low quantities, the result is a serious disease called diabetes mellitus. The Greek name "pancreas", meaning "all flesh" or "all meat", is descriptive of the protein composition of this powerful organ which resembles a fish with a large head and a long tail. Inside, the organ's appearance resembles a stalk with clusters of grapes attached to it. The "stalk" is a long duct which runs down the center of the pancreas and the "grapes" are clusters of cells which flow into this duct and later into the duodenum for digestion of proteins, fats and carbohydrates. If the ducts leading from the pancreas are blocked in some way, the digestive fluids build up in the pancreas and may then become activated so that they digest the pancreas itself! This condition is known as acute pancreatitis. Pancreatic cancer has the worst prognosis of all the types of cancer. This is probably because of the spongy, vascular nature of this organ and its vital endocrine and exocrine functions. Pancreatic surgery is a problem because of the soft, spongy, tissue it consists of that make it extremely difficult to suture. By the way, Webster's Dictionary says the "pancratium" was an ancient Greek athletic contest involving boxing and wrestling. Isn't that interesting?

Pyloric Region

The pyloric region is at the top of the stomach and narrows to become the "pyloric canal" as it approaches the junction with the small intestine. At the end of the pyloric canal, the circular layer of fibers in its muscular wall is thickened, forming a powerful muscle called the "pyloric sphincter." This muscle serves as a valve that prevents regurgitation of food from the intestine back into the stomach.