Exam 5 Review:  Chapter 16:  The Pancreas and Diabetes Mellitus

pancreatic islets = Islets of Langerhans - Any of several masses of endocrine cells in the pancreas including alpha cells which secrete the protein hormone glucagon, beta cells which secrete the protein hormone insulin, and delta cells which secrete the protein hormone somatostatin.

acinar cells - The pancreatic exocrine secretory cells attached to the pancreatic duct system; these cells secrete a variety of digestive enzymes which are transported to the duodenum.

α cell - Those endocrine cells in the pancreatic islets which secrete that secrete the protein hormone glucagon.

β cell - Those endocrine cells in the pancreatic islets which secrete that secrete the protein hormone insulin.

glucagon - The protein hormone secreted by the alpha cells of the pancreatic islets of Langerhans; it is an insulin antagonist, raising the concentration of glucose in the blood by targeting the liver to promote glycogenolysis, i.e., the degradation of glycogen to glucose, and gluconeogenesis, the synthesis of new glucose from non-carbohydrate precursors; it uses cyclic AMP as its second messenger.

insulin - The protein hormone secreted by the beta cells of the pancreatic islets of Langerhans; it reduces the concentration of glucose in the blood by targeting the liver to promote glycogenesis, i.e., the formation of glycogen from glucose, and it targets most cells of the body, other than nervous tissue, to take glucose from the blood and use it as metabolic fuel; its deficiency or failure to perform causes the disease diabetes mellitus.

glycogenolysis - The enzymatic breakdown of glycogen to release glucose from the liver which is triggered by the action of various hormones, e.g., glucagon, human growth hormone, glucocorticoids, and the "catecholamines, epinephrine = adrenalin and norepinephrine, which may all be referred to as “insulin antagonists.”

diabetes mellitus -  A group of chronic disorders of glucose metabolism caused by inadequate production or use of insulin, the hormone produced in the beta cells in the pancreas islets which allows the body to use and store glucose; it is a leading cause of death in the United States and is especially prevalent among African Americans.

polyuria - The production and passing of an excessive quantity of urine, a symptom in diabetes mellitus, diabetes insipidus, in certain nervous diseases, etc.

polydipsia - Excessive thirst and excessive consumption of liquids as a result, a symptom in diabetes mellitus, diabetes insipidus, in certain nervous diseases, etc.

polyphagia - An excessive desire to eat and excessive eating as a result of a disease process, e.g., diabetes mellitus.

insulin-dependent diabetes mellitus ["juvenile diabetes"] = Type I diabetes mellitus - An autoimmune disease in which autoantibodies attack beta cells in the pancreatic islets causing the pancreas to be able to make little or no insulin; the only effective therapy is insulin replacement therapy; symptoms of this disease include polyuria, polyphagia, polydipsia, and a chronic and severe hyperglycemia; only 5-10% of people with diabetes mellitus have this type.

ketoacidosis. - An acidosis (an abnormal increase in the acidity, i.e., hydrogen ion concentration, in the body fluids) with an accumulation of ketone bodies; it occurs primarily in untreated or out-of-control diabetes mellitus.

non-insulin-dependent diabetes mellitus ["adult/maturity-onset"] =  Type II diabetes mellitus - A disease in which beta cells in the pancreatic islets may make too little insulin or the target cells in the body do not respond appropriately to insulin; the effective therapies begin with control of diet and exercise, include anti-hyperglycemic oral medications, and, perhaps, eventually insulin replacement therapy; symtoms of this disease include polyuria, polyphagia, polydipsia, and a chronic and severe hyperglycemia;  90-95% of people with diabetes mellitus have this type.

gestational diabetes - A form of diabetes mellitus which develops during pregnancy, generally during the second half; it affects about 4 percent of pregnant women; it develops when hormones secreted during pregnancy increase the pregnant female's body's resistance to insulin; it usually goes away after pregnancy, but more than half of all women with gestational diabetes eventually develop type II diabetes.

hyperinsulinism - An abnormally high level of insulin in the blood, resulting in hypoglycemia, which, if it becomes severe enough, may lead to an insulin shock coma.

hypoglycemia - An abnormally low level of glucose in the blood, usually resulting from excessive insulin or a poor diet, which may produce headache and feelings of faintness.

insulin shock - Acute hypoglycemia usually resulting from an overdose of insulin and characterized by sweating, trembling, dizziness, and, if left untreated, convulsions and coma.

List

          glucagon, human growth hormone, glucocorticoids (cortisol, etc.), epinephrine & norepinephrine

Sketch and label:

5. the pancreas illustrating the distribution of its exocrine vs. endocrine tissues.

 

The pancreatic acinar tissue (exocrine) is indicated in yellow; the pancreatic duct system in gold on the red, the gall bladder is the green structure at the lower left, and the many purple dots represent the many pancreatic islets (endocrine) distributed at random throughout the bulk of the pancreatic tissue.  The red tubular segments represent portions of the duodenum of the small intestine.