Alpha cells, pancreas

Q13 The pancreas produces hormones in areas of endocrine tissue the islets of Langerhans. The major hormones are insulin, from the beta-cells (/0-cells), and glucagon, from alpha-cells (a-cells). Delta cells produce somatostatin. 

Expression of Kd -Cl- cotransporters in the [alpha]-cells of rat endocrine pancreas. Biochim Biophys Acta (BBA)-Biomembranes 1667 7-14. 

Peptide YY (PYY) Enteroendocrine cells, developing pancreas alpha cells in mature islets 1. Inhibits both gastric acid secretion and gastric motility 2. Slows intestinal motility 3. Inhibits pancreatic exocrine secretion 1. Oral nutrient ingestion 2. Bile acids and fatty acids 3. Amino acids in colon... 

Homeostatic Hormones. Insulin is produced by beta cells found in the islets of Langerhans that are dispersed throughout the pancreas. The islet cells constitute only 1% of total pancreatic tissue. Each islet contains about 3000 endocrine cells with a core of beta cells surrounded by other endocrine cells such as the glucagon-secreting alpha cells, the somatostatin-secreting delta cells, and the pancreatic polypeptide-secreting PP cells. The beta cells first synthesize a 109-amino-acid preproinsulin that is subsequently processed to an 86-amino-acid proinsulin. The... 

Glucagon is a hyperglycemic hormone secreted by the alpha cells of the islets of Langerhans in the pancreas and increases blood sugar by stimulating glycogenolysis (glycogen breakdown) in the liver. 

In the 1920 s when pure preparations of insulin were difficult to obtain, some preparations for intravenous administration were shown to contain a hyperglycemic factor that was later named glucagon. The factor was purified from insulin preparations and crystallized in 1953. Glucagon is a straight chain polypeptide hormone composed of 29 amino acids and devoid of disulfide bonds. It is elaborated in the alpha cells of the islet of the pancreas and is extractable from pancreas after beta cell destruction. 

Necrolytic migratory erythema is usually part of the glucagonoma syndrome, which is characterized by an alpha cell tumor of the pancreas, leading to adult onset diabetes mellitus, weight loss, and glossitis. It is often mistaken for intertrigo or seborrheic dermatitis. Its pathogenesis is not well understood. The role of opiates in this case was not clear, but it was not due to poor nutrition or poor absorption of nutrients. The authors speculated that opiates had had a direct effect on epidermal metabohsm. 

Denker SP, McCaffery JM, Palade GE, Insel PA, Farquhar MG (1996) Differential distribution of alpha subunits and beta gamma subunits of heterotrimeric G proteins on Golgi membranes of the exocrine pancreas. J Cell Biol 133 1027-1040... 

An important interaction between insulin and glucagon may also take place directly within the pancreas, and insulin appears to be the dominant hormone controlling this interaction.29,53 When the beta cells sense an increase in blood glucose, they release insulin, which in turn inhibits glucagon release from the alpha... 

Zinc snlfate is absorbed poorly from the G1 tract only 20 to 30% of dietary zinc is absorbed. After administration, zinc resides in mnscle, bone, skin, kidney, liver, pancreas, retina, prostate, and, particnlarly, red and white blood cells. Zinc binds to plasma albnmin, alpha-2 macroglobulin, and some plasma amino acids inclnding histidine, cysteine, threonine, glycine, and asparagine. 

Pancreas Left of and behind the stomach (exocrine and endocrine gland) Exocrine secretes digestive enzymes into the duodenum Endocrine has cell clusters called islets of Langerhans alpha islet cells produce glucagons beta cells secrete insulin... 

The effects on plasma insulin and glucagon result from a direct action of GH-RIH on the alpha and beta cells of the pancreas since they have been demonstrated by direct perfusion experiments with the isolated canine pancreas (Al, 12). 

Islats of Langarhans Smallgroupsof cells In the pancreas that function as an endocrine gland. The alpha (or A) cells secrete the hormone glucagon, the beta (or B) cells secrete Insulin, and the D cells secrete somatostatin. The Islets are named after their discoverer, the German anatomist and mi-croscopist Paul Langerhans (1847-88). 

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