Pancreas insulin

Insulin is necessary for controlling type 1 diabetes mellitus that is caused by a marked decrease in the amount of insulin produced by die pancreas. Insulin is also used to control the more severe and complicated forms of type 2 diabetes mellitus. However, many patients can control type 2 diabetes with diet and exercise alone or with diet, exercise, and an oral antidiabetic drug (see section Oral Antidiabetic Dmgp ). Insulin may also be used in the treatment of severe diabetic ketoacidosis (DKA) or diabetic coma. Insulin is also used in combination with glucose to treat hypokalemia by producing a shift of potassium from die blood and into die cells. 

Insulin is a polypeptide hormone produced by the p cells of the islets of Langerhans—clusters of cells that are embedded in the exocrine por fon of the pancreas (Figure 23.2). The islets of Langerhans make up only about one to two percent of the total cells of the pancreas. Insulin... 

Insulin, the first polypeptide hormone to be identified, was discovered by Frederick G. Banting and Charles Best in 1922. They found that this substance, which they isolated from the pancreas, restored normal glucose utilization in experimental animals lacking a pancreas. Insulin was also the first protein to be sequenced, a landmark accomplishment achieved by Fred Sanger in 1955. About 20 years... 

Insulin is a storage hormone produced by the pancreas. Insulin shuttles nutrients, such as carbohydrates, fats and amino acids (derived from proteins) into cells. The main function of insulin is to maintain homeostasis of circulatory glucose, and intracellular glycogen storage. It also aids in fat storage. 

For the first time in history there was clear, unambiguous clinical evidence, in humans, that symptoms of diabetes mellitus could be controlled with the exogenous administration of the active factor of the pancreas—insulin. Thus, replacement therapy with the newly discovered hormone, insulin, had arrested what was clearly an otherwise fatal metabolic disorder. From that point forward, diabetes mellitus (type 1) became a manageable disease by pharmacological intervention. 

Insulin and glucagon are polypeptide hormones synthesized in, and secreted by, the pancreas. Insulin is produced by the / cells of the pancreas, and glucagon by the a cells. The secretion of either of these hormones depends on the blood glucose concentration above 4.5-5.5 mM (80-100 mg/100 mL) of glucose, insulin is secreted, but below 4.5 mA/ (80 mg/100 mL). glucagon is secreted. 

COMPOUNDS ACTING IN THE PANCREAS INSULIN SECRETION 02-Antagonists and imidazolines Animal studies Compounds studied clinically Glucagon-like peptides... 

In the treatment of diseases where the metabolites are not being delivered to the system, synthetic metabolites or active analogues have been successfully administered. Vitamin D3 metabolites have been successfully used for treatment of milk fever in catde, turkey leg weakness, plaque psoriasis, and osteoporosis and renal osteodystrophy in humans. Many of these clinical studies are outlined in References 6, 16, 40, 51, and 141. The vitamin D receptor complex is a member of the gene superfamly of transcriptional activators, and 1,25 dihydroxy vitamin D is thus supportive of selective cell differentiation. In addition to mineral homeostasis mediated in the intestine, kidney, and bone, the metabolite acts on the immune system, p-cells of the pancreas (insulin secretion), cerebellum, and hypothalamus. 

Insuhn is a protein hormone produced by the (5-ceUs of the islets of Langerhans in the pancreas. Insulin was the first protein hormone to be sequenced, the first substance to be measured by radioimmunoassay (RIA), and the first compound produced by recombinant DNA technology for practical use. It is an anaboUc hormone that stimulates the uptake of glucose into fat and muscle, promotes the conversion of glucose to glycogen or fat for storage, inhibits glucose production by the liver, stimulates protein synthesis, and inhibits protein brealcdown. 

Chicco A, D Alessandro ME, Karabatas L, Gutman R, Lombardo YB. Effect of moderate levels of dietary fish oil on insulin secretion and sensitivity, and pancreas insulin content in normal rats. Ann Nutr Metab 1996 40 61-70. 

Insulin A polypeptide hormone synthesized and secreted by the p-cells of the islets of Langerhans in the pancreas. Insulin is released in response to elevations in blood glucose and promotes the uptake of glucose into cells by increasing the number of GLUT 4 glucose transporters on cell surfaces. 

Pancreas Insulin General anabolic effects including glucose uptake and lipogenesis... 

Insulin Beef or pork pancreas Insulin Acidic alcohol ... 

Am. These hormones are polypeptides, and secreted by the pancreas. Insulin is synthesized and secreted by the )3-cells, and glucagon by the a-cells. Their secretion into the blood is directly controlled by the blood glucose concentration. Above 80 to 100 mg percent, the pancreatic a-cells secrete insulin. Below that level, the a-cells secrete glucagon. That blood glucose concentration is optimum for brain function. 

The dynamic process in which body proteins are continuously hydrolyzed and resynthesized is called protein turnover. The turnover rate, or life expectancy, of body proteins is a measure of how fast the proteins are broken down and resynthesized. The turnover rate is usually expressed as a half-life. The use of radioactive amino acids has enabled researchers to estimate half-lives by measuring the exchange rate between body proteins and the amino acid pool. For example, the half-life of liver proteins is about 10 days. This means that over a 10-day period, half the proteins in the liver are hydrolyzed to amino acids and replaced by equivalent proteins. Plasma proteins also have a half-life of about 10 days, hemoglobin about 120 days, and muscle protein about 180 days. The half-life of collagen, a protein of connective tissue, is considerably longer—some estimates are as high as 1000 days. Other proteins, particularly enzyme and polypeptide hormones, have much shorter half-lives of only a few minutes. Once it is released from the pancreas, insulin has a half-life estimated to be only 7-10 minutes. 

The increased concentration of glucose and amino acids in the portal blood stimulates the P-cells of the pancreas to secrete insulin, and suppresses the secretion of glucagon by the a-cells of the pancreas. Insulin has four main actions ... 

Pancreas Insulin, glucagon, somatostatin, pancreatic polypeptide... 

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