Hormones and Diseases in the Digestive System Amy Lee Lily Lee Alex Lopez

Hormones

Gastric Hormones Gastrin: peptide hormone that stimulates secretion of gastric acid Incretin: Incretins are a group of gastrointestinal hormones that cause an increase in the amount of insulin released. They also slow the rate of absorption of nutrients into the blood stream by reducing gastric emptying and may directly reduce food intake. As expected, they also inhibit glucagon

Hormones of the Liver Androsterone: (ADT) is a steroid hormone with weak androgenic activity. It is made in the liver from the metabolism of testosterone. Medullipin:  is a hormone created by the interstitial cells of renal papilla, which is converted to medullipin II in the liver. This, in turn, results in vasodilation and decreased blood pressure.

Intestinal Hormones N-Acylphosphatidylethanolamine: Hormones released by the small intestine into the bloodstream when it processes fat. NAPEs travels to the hypothalamus in the brain and suppress appetite. This mechanism could be relevant for treating obesity Cholecystokinin: is a peptide hormone of the gastrointestinal system responsible for stimulating the digestion of fat and protein. It also causes the release of digestive enzymes and bile from the pancreas and gallbladder. Motilin: is secreted by endocrine M cells that are numerous in crypts of the small intestine, especially in the duodenum and jejunum. Base d on amino acid sequence, motilin is unrelated to other hormones.

Secretin Secreted by upper wall of small intestine Function: causes pancreas to send out a digestive juice that is rich in bicarbonate. The bicarbonate helps neutralize the acidic stomach contents as they enter the small intestine. also stimulates the stomach to produce pepsin(enzyme that digests protein) and stimulates the liver to produce bile History: Sir William M. Bayliss & Ernest H. Starling (physiologists) discovered secretin by placing dilute hydrocholoric acid into a segment of a dog’s bowel lining Injected that into another dog. Result = increase in secretion of pancreatic juice in the dog receiving injection The name “secretin” comes from the material in the extract.

Vasoactive intestinal peptide Role in the intestine: - to greatly stimulate secretion of water and electrolytes - stimulating contraction of enteric smooth muscle - dilating peripheral blood vessels -stimulating pancreatic bicarbonate secretion - Inhibiting gastrin-stimulated gastric acid secretion. Produced in the gut, pancreas and hypothalamus. Stimulates contractility in the heart causes vasodilation increases glycogenolysis lowers arterial blood pressure relaxes the smooth muscle of trachea, stomach and gall bladder ^These effects work together to increase motility Stimulate secretion of water into pancreatic juice and bile Causes inhibition of gastric acid secretion and absorption from the intestinal lumen

Pancreatic polypeptide Secreted by the pancreas Reduces appetite and food intake in humans. Function: to self regulate the pancreas secretion activities (endocrine and exocrine) Also has effects on hepatic glycogen levels and gastrointestinal secretions Its secretion in humans is increased after a protein meal, fasting, exercise, and acute hypoglycemia and is decreased by somatostatin and intravenous glucose.

Somatostatin Secreted in several locations in the digestive system stomach, intestine, delta cells of the pancreas Important for the control of the human digestive system Aids in the control of the rate of digestion ensures that the amt of digestive hormones is not excessive GHIH helps to reduce the flow of blood to the intestine, also to reduce the muscle contractions of the stomach

Diseases

Crohn’s Disease “Reginoal Enteritis” Type of inflamatory bowel disease Symptoms: Abdominal pain Diarhea Vomiting Weightloss

Crohn’s Treatments: Diet and Nutrition Controlling Stress Medication Surgery

Gastroesophageal Reflux Disease a chronic symptom of mucosal damage caused by stomach acid coming up from the stomach into the esophagus. Regurgitation Trouble Swallowing Chest pain Ulcers Symptoms: Heartburn

Gastroesophageal Reflux Disease Treatment: Lifestyle: Diet Position of Sleep-left Medication Surgery image of peptic stricture, or narrowing of the esophagus near junction with stomach

Peptic Ulcer Most Common Acidic and extremely painful Types: 2: Ulcer in the body in combination with duodenal ulcers. Associated with acid over secretion Acidic and extremely painful 3: In the pyloric channel within 3 cm of pylorus. Associated with acid oversecretion Types: 1: Ulcer along the body of the stomach, most often along the lesser curve at incisura angularis along the locus minoris resistantiae 4: Proximal gastroesophageal 5: Can occur throughout the stomach. Associated with chronic NSAID use (such as aspirin).

Peptic Ulcer Symptoms: Treatment Complications Gastrointestinal bleeding Abdominal pain Perforation (hole) Bloating Cancer Nausea Penetration Vomiting of blood Scarring Treatment Surgery Antacids Nonsteroidal anti- inflammatories Complications

Bibliography http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0 001295/ http://www.anaspec.com/products/productcate gory.asp?id=184 http://www.ccfa.org/info/about/crohns http://en.wikipedia.org/wiki/Vasoactive_intestin al_peptide http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0 001311/ http://en.wikipedia.org/wiki/Pancreatic_polypep tide http://digestive.niddk.nih.gov/ddiseases/pubs/gerd/ http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0 001255/ http://www.uptodate.com/contents/vasoactive- intestinal-polypeptide http://www.webmd.com/digestive- disorders/digestive-diseases-peptic-ulcer-diseas http://www.vivo.colostate.edu/hbooks/pathphy s/endocrine/gi/secretin.html http://www.vivo.colostate.edu/hbooks/pathphy s/endocrine/gi/secretin lhttp://www.uptodate.com/contents/vasoactive -intestinal-polypeptide