Endocrine Pancreas

Question 1

Long term marker of endogenous insulin secretion

Answer 1

C-peptide

Question 2

Factors that inhibit insulin secretion

Answer 2

• Somatostatin

- Norepinephrine (Alfa-receptor) [SANS]

Question 3

What stimuli increases and inhibits secretion of glucagon?

Answer 3

• increases: hypoglycemia, basic AA (arginine, lysine)

- decreases: hyperglycemia, insulin, somatostatin

Question 4

Why does the coma occur in case of diabetes?

Answer 4

Hyperosmotic environment, not acidosis

Question 5

Why you may repose potassium before or during insulin replacement in diabetes mellitus patient?

Answer 5

• previous hypokalemia although plasma levels above or normal
• sudden insulin replacement can produce severe hypokalemia

Question 6

How does the glucagon favor the formation of ketone bodies in context of insulin absence and then ketoacidosis diabetes?

Answer 6

Glucagon ▶️ (-) acetyl CoA carboxylase ▶️ ⬇️ Malonyl CoA

*when Malonyl CoA ⬇️ ketogenesis is favored over lipogenesis

Question 7

How do you differentiate a hypoglycemia due to an insulinoma or factitious hypoglycemia?

Answer 7

• insulinoma: insulin and c-peptide ⬆️

- factitious hypoglycemia: c-peptide normal

Question 8

Why is rare that in type 2 diabetes ketoacidosis occur unless very stressful situation?

Answer 8

A little amount of insulin may be protective to ketogenesis

*insulin (-) lipolysis ▶️ (-) HSL