Islet cell structure α cell : glucagon β cell : insulin δcell : somatostatin α cell β cell...

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  • Islet cell structure cell : glucagon cell : insulincell : somatostatin cell cellcell

  • Principal actions of insulinIts net effect is to promote the storage of carbohydrate, protein and fat. It is therefore appropriately called the hormone of abundance.70 mg/dl300 mg/dl(Glucosurea)

  • Consequences of insulin deficiencyNORMALDIABETIC

  • Disturbances in protein metabolismINSULIN DEFICIENCY

  • Dehydration

  • Insulinlipodystrophy

  • Chronic neuropathy:Trophic ulceration

  • Gangrene

  • Gangrene with infection

  • Insulin allergy

  • Glucagon Synthesis and secretion of glucagon GlucagonAmino acidsGlucoseFFAKetoacid

  • Actions of glucagon Plasma: Glucose Amino acids Free fatty acids

  • Diabetic retinopathy Microvascular complication

  • Hormones of the pancreatic isletsPancreas, Liver & NutrientLiver : the central organ in nutrient traffic

  • Endocrine regulation of carbohydrate metabolismInsulinGlucagonSomatostatin --- inhibit the secretion of insulin & glucagonEpinephrine --- cyclic AMP increased, [Ca+2] increased hepatic glucose output increased.5. thyroid hormone : (1) increases the absorption of glucose from the intestine (2) cause hepatic glycogen depletion (3) accelerate the degradation of insulin6. glucocorticoids --- diabetogenic effect7. growth hormones --- inhibition of glucose phosphorylation decrease utilization

  • In SummaryInsulinIs released by B-cells in the Islets of Langerhans in the pancreas.Responds to high levels of blood sugar; is released when someone has a meal and needs to store extra energy.Lack of insulin or response to insulin leads to diabetes.GlucagonIs released by a-cells in the Islets of Langerhans in the pancreas.Responds to low levels of blood sugar; is released when someone hasnt eaten or requires extra energyBasically, glucagon is the opposite of insulin.