G cellIn anatomy, the G cell or gastrin cell, is a type of cell in the stomach and duodenum that secretes gastrin. It works in conjunction with gastric chief cells and parietal cells. G cells are found deep within the pyloric glands of the stomach antrum, and occasionally in the pancreas and duodenum. The vagus nerve innervates the G cells. Gastrin-releasing peptide is released by the post-ganglionic fibers of the vagus nerve onto G cells during parasympathetic stimulation. The peptide hormone bombesin also stimulates gastrin from G cells.
OmeprazoleOmeprazole, sold under the brand names Prilosec and Losec, among others, is a medication used in the treatment of gastroesophageal reflux disease (GERD), peptic ulcer disease, and Zollinger–Ellison syndrome. It is also used to prevent upper gastrointestinal bleeding in people who are at high risk. Omeprazole is a proton-pump inhibitor (PPI) and its effectiveness is similar to that of other PPIs. It can be taken by mouth or by injection into a vein.
CyanocobalaminCyanocobalamin is a form of vitamin B12 used to treat vitamin B12 deficiency except in the presence of cyanide toxicity. The deficiency may occur in pernicious anemia, following surgical removal of the stomach, with fish tapeworm, or due to bowel cancer. It is less preferred than hydroxocobalamin for treating vitamin B12 deficiency. Some study have shown that it has an antihypotensive effect. It is used by mouth, by injection into a muscle, or as a nasal spray. Cyanocobalamin is generally well tolerated.
HistamineHistamine is an organic nitrogenous compound involved in local immune responses communication, as well as regulating physiological functions in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Since histamine was discovered in 1910, it has been considered a local hormone (autocoid) because it lacks the classic endocrine glands to secrete it; however, in recent years, histamine has been recognized as a central neurotransmitter. Histamine is involved in the inflammatory response and has a central role as a mediator of itching.
DigestionDigestion is the breakdown of large insoluble food molecules into small water-soluble food molecules so that they can be absorbed into the watery blood plasma. In certain organisms, these smaller substances are absorbed through the small intestine into the blood stream. Digestion is a form of catabolism that is often divided into two processes based on how food is broken down: mechanical and chemical digestion. The term mechanical digestion refers to the physical breakdown of large pieces of food into smaller pieces which can subsequently be accessed by digestive enzymes.
Proton-pump inhibitorProton-pump inhibitors (PPIs) are a class of medications that cause a profound and prolonged reduction of stomach acid production. They do so by irreversibly inhibiting the stomach's H+/K+ ATPase proton pump. They are the most potent inhibitors of acid secretion available. Proton-pump inhibitors have largely superseded the H2-receptor antagonists, a group of medications with similar effects but a different mode of action, and antacids. PPIs are among the most widely sold medications in the world.
Pernicious anemiaPernicious anemia is a disease in which not enough red blood cells are produced due to a deficiency of vitamin B12. Those affected often have a gradual onset. The most common initial symptoms are feeling tired and weak. Other symptoms of anemia may include shortness of breath, lightheadedness, headaches, sore red tongue, cold hands and feet, pale or yellow skin, chest pain, and an irregular heartbeat. The digestive tract may also be disturbed giving symptoms that can include nausea and vomiting, heartburn, upset stomach and loss of appetite.
Megaloblastic anemiaMegaloblastic anemia is a type of macrocytic anemia. An anemia is a red blood cell defect that can lead to an undersupply of oxygen. Megaloblastic anemia results from inhibition of DNA synthesis during red blood cell production. When DNA synthesis is impaired, the cell cycle cannot progress from the G2 growth stage to the mitosis (M) stage. This leads to continuing cell growth without division, which presents as macrocytosis. Megaloblastic anemia has a rather slow onset, especially when compared to that of other anemias.
SecretinSecretin is a hormone that regulates water homeostasis throughout the body and influences the environment of the duodenum by regulating secretions in the stomach, pancreas, and liver. It is a peptide hormone produced in the S cells of the duodenum, which are located in the intestinal glands. In humans, the secretin peptide is encoded by the SCT gene. Secretin helps regulate the pH of the duodenum by (1) inhibiting the secretion of gastric acid from the parietal cells of the stomach and (2) stimulating the production of bicarbonate from the ductal cells of the pancreas.
Atrophic gastritisAtrophic gastritis is a process of chronic inflammation of the gastric mucosa of the stomach, leading to a loss of gastric glandular cells and their eventual replacement by intestinal and fibrous tissues. As a result, the stomach's secretion of essential substances such as hydrochloric acid, pepsin, and intrinsic factor is impaired, leading to digestive problems. The most common are vitamin B12 deficiency possibly leading to pernicious anemia; and malabsorption of iron, leading to iron deficiency anaemia.
