Stomach - a hollow body which is adapted for filling with food, the initial digestion, partial absorption of nutrients from the further evacuation of the contents of the duodenum. Located in the stomach, upper abdomen, below the diaphragm, mostly to the left of the midline. The shape and volume of the stomach depends on the tone of his muscles, by filling it with food, the state of the neighboring organs, the position of the body. In the upper part of the stomach empties into the esophagus it at the bottom of the stomach moves duodenum.
The stomach is divided into four parts.
Cardiac part of stomach is above and adjacent to the opening of the esophagus to the stomach, called the "cardia".
The bottom or set - part of the stomach, which is located at the top and forms a kind of dome.
The body of the stomach is the main central part of the stomach.
Privratnikovaya or pyloric portion is located at the entrance to the duodenum, where the sphincter that regulates the flow of bolus into the duodenum - the pylorus.
The wall of the stomach consists of four layers:
mucosal
submucosal layer
muscle layer
outer serous membrane.
Gastric mucosa is a layer on top of which are cylindrical epithelial cells, beneath which is a loose connective tissue and then a thin layer of smooth muscle. In the loose connective tissue of the mucous membrane are cancer of the stomach.
There are three types of cells that form these glands. Some of them are called the principal. These glands produce pepsinogen and chymosin. The next type of cells called parietal or parietal cells. They carried out the synthesis of hydrochloric acid and gastromukoproteina. The third type of cell - is additional cells or mukotsity. They produce mucoid secret. In the pylorus (pylorus) are hormonally active cells. These cells synthesize gastrin.
In the mucosa is also producing a huge number of other biologically active substances. The role of some of them are still not fully understood. A very important function of the glandular cells of the stomach is the formation of protective mucus barrier. Requires continuous synthesis of gastric mucus, which is produced blennogenic cells.
Stimulate the function activating effects of the autonomic nervous system, insulin, serotonin, prostaglandins. Increases mucus production by the mechanical action of irritating gastric mucosa of the food bolus. Reduce blennogenic feature some of the medications: aspirin (acetylsalicylic acid), non-steroidal anti-inflammatory drugs, etc.
