Digestion in the Stomach

Water, alcohol, salt, and simple sugars can be absorbed directly through the stomach wall. However, most substances in our food need a little more digestion and must travel into the intestines before they can be absorbed.

Doctors often treat an H. pylori infection by prescribing antibiotics as well as medications that suppress acid production in the stomach. A popular medication is a type known as a proton pump inhibitor, which blocks the production of hydrochloric acid.

Accordingly, intragastric administration of HCl at concentrations of 0.15 – 0.5 M to conscious rats elicits a visceromotor response indicative of pain (22) and causes many neurons in the nucleus of the solitary tract in the rat brainstem to express c-Fos, a marker of neuronal excitation (34). The gastric HCl-evoked visceromotor reaction and medullary c-Fos response are suppressed by vagotomy, but not transection of the sympathetic nerve supply to the stomach, which indicates that gastric HCl-evoked nociception depends critically on the integrity of the vagal afferent innervation (22,34). passage from the stomach to the duodenum through coordinated activity of the lower esophageal (LES) and pyloric sphincter. Both sphincters are under the control of neural reflexes involving acid-sensitive neurons which adjust the tone of the LES and pyloric sphincter to balance the levels of acid present in the esophagus, stomach and duodenum with the mucosal defense mechanisms in these compartments (11,14).

The stomach is a thick walled organ that lies between the esophagus and the first part of the small intestine (the duodenum). It is on the left side of the abdominal cavity, the fundus of the stomach lying against the diaphragm.

In summary, HCl in the stomach lumen accomplishes four things. It helps break down ingested tissues for attack by digestive enzymes; it provides the correct pH for the action of those enzymes; it converts a catalytically inactive proenzyme to an active enzyme (as we just saw); and it destroys invading microorganisms in the stomach contents.

Here, the acid would present a hazard to the intestinal epithelium, so it is neutralized by added secretions, in part composed of bicarbonate (which is basic) from the pancreatic duct. The liver produces yet another digestive juice – bile. The bile is stored between meals in the gallbladder.

Gastric Phase

An ulcer is a sore that forms on the stomach lining or on the lining of the duodenum (the first part of the small intestine). Ulcers in the stomach are known as stomach, gastric, or peptic ulcers. Ulcers in the duodenum are known as peptic or duodenal ulcers. The inside of the stomach is a very acidic environment, especially after food has just been eaten. The acidic pH is created by hydrochloric acid, which is secreted by cells in the stomach lining.

In its course, describes an arch which surrounds the convolutions of the small intestine. It commences in the right iliac region, in a dilated part, the cecum. It ascends through the right lumbar and hypochondriac regions to the under surface of the liver; here it takes a bend, the right colic flexure, to the left and passes transversely across the abdomen on the confines of the epigastric and umbilical regions, to the left hypochondriac region; it then bends again, the left colic flexure, and descends through the left lumbar and iliac regions to the pelvis, where it forms a bend called the sigmoid flexure; from this it is continued along the posterior wall of the pelvis to the anus.

Esophageal cancer. This form of cancer may not be diagnosed until it’s quite advanced. The possible link between bile and acid reflux and esophageal cancer remains controversial, but many experts think a direct connection exists. In animal studies, bile reflux alone has been shown to cause cancer of the esophagus.

The symptoms can be managed by following a gluten free diet. Doctors can diagnose this condition by taking a full medical history or with a blood test. The liver is an organ in vertebrates, including human. It plays a major role in metabolism and has a number of functions in the body including glycogen storage, plasma protein synthesis, and drug detoxification.

a thick semifluid mass of partially digested food and digestive secretions that is formed in the stomach and intestine during digestion. In the stomach, digestive juices are formed by the gastric glands; these secretions include the enzyme pepsin, which breaks down proteins, and hydrochloric acid. Once food is in the small intestine, it stimulates the pancreas to release fluid containing a high concentration of bicarbonate. This fluid neutralizes the highly acidic gastric juice, which would otherwise damage the membrane lining of the intestine, resulting in a duodenal ulcer. Other secretions from the pancreas, gallbladder, liver, and glands in the intestinal wall add to the total volume of chyme.

There is a common misconception that enzymes are destroyed by stomach acid. Nothing could be further from the truth. Stomach acid does not digest protein. Rather, it activates an enzyme called pepsinogen which then becomes pepsin that is secreted by the stomach wall. This enzyme is only active within the pH range of 3.0 to 5.0 and requires the acid to maintain that pH. Pepsin is very specific in its action and is simply incapable of digesting food enzymes, which are very large molecules and are more than just protein.

The stomach participates in all digestive activities except ingestion and defecation. It vigorously churns food. It secretes gastric juices that break down food and absorbs certain drugs, including aspirin and some alcohol. The stomach begins the digestion of protein and continues the digestion of carbohydrates and fats. It stores food as an acidic liquid called chyme, and releases it gradually into the small intestine through the pyloric sphincter.

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