Diabetes Mellitus Q 30

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Marlisa has been diagnosed with diabetes mellitus type 1. She asks Nurse Errol what this means. What is the best response by the nurse? Select all that apply.

  

    A. "Your alpha cells should be able to secrete insulin, but cannot."

    B. "The exocrine function of your pancreas is to secrete insulin."

    C. "Without insulin, you will develop ketoacidosis (DKA)."

    D. "The endocrine function of your pancreas is to secrete insulin."

    E. "It means your pancreas cannot secrete insulin."

    

Correct Answer: C, D, & E

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One function of your pancreas is to secrete insulin. The endocrine function of the pancreas is to secrete insulin. A consequence of diabetes mellitus type 1 is that without insulin, severe metabolic disturbances, such as ketoacidosis (DKA) will result.

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Option A: Insulin is secreted by the beta, not the alpha, cells of the pancreas. Insulin synthesis occurs in the beta cells of the pancreas initially as preproinsulin. Preproinsulin then converts to proinsulin, which then transforms into a single peptide with A, B, and C peptide units.

Option B: The pancreas contains exocrine glands that produce enzymes important to digestion. These enzymes include trypsin and chymotrypsin to digest proteins; amylase for the digestion of carbohydrates; and lipase to break down fats.

Option C: Insulin deficiency and increased counterregulatory hormones also lead to the release of free fatty acids into circulation from adipose tissue (lipolysis), which undergo hepatic fatty acid oxidation to ketone bodies (beta-hydroxybutyrate and acetoacetate), resulting in ketonemia and metabolic acidosis.

Option D: The endocrine, not the exocrine, function of the pancreas is to secrete insulin. The endocrine component of the pancreas consists of islet cells (islets of Langerhans) that create and release important hormones directly into the bloodstream. Two of the main pancreatic hormones are insulin, which acts to lower blood sugar, and glucagon, which acts to raise blood sugar.

Option E: Three mechanisms lead to islet cell destruction: genetic susceptibility, autoimmunity, and environmental insult(s). A virus or allergen (environmental insults) in genetically susceptible individuals induces the production of autoantibodies to Beta cells of the islets of the pancreas. This autoimmune reaction creates autoreactive T cells that destroy beta-islet cells and cause loss of insulin secretion.

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