Functional pancreatic neuroendocrine tumors (pNETs) present with symptoms related to ________
Excessive circulating hormones
Symptoms of non-funcitonal pNETs arise _____
From the tumor
T/F: only functional pNETs can be metastatic
False; both functional and non-functional can be
Insulinomas would ____ level of insulin during hypoglycemia state
Increase
Which could lead to insulin shock and CNS depression
What is insulinoma?
pNET that secretes excessive amounts of insulin, leading to hypoglycemia
how is insulinoma diagnosed?
elevated plasma insulin during hypoglycemia; whereas in a healthy person, in hypoglycemic state, the level of insulin should decrease
What are glucagonomas?
Glucagon secreting tumors of the pancreas
T/F: Glucagonomas would increase blood sugar and lead to decreased lipolysis and resulting in weight gain
False; glucagonomas increases blood sugar, and would increase lipolysis which results in weight loss
Necrolytic migran erythema is associated with which pNET?
Glucagonoma
Zollinger-Ellison syndrome is ____
Gastrinoma secreting excessive amount of gastrin
What effect does gastrinoma have on parietal cells?
Increase gastrin which would increases HCl secretion from stomach parietal cells and leading to ulcers in the duodenum
T/F: high volume of gastric acid secretion in the stomach may leak into the esophagus, producing heartburn
True
Gastric acid secretion, at high volume, can leak into ___ and ____
Esophagus
Duodenum- generating peptic ulcer disease
Why is steatorrhea a symptom of gastrinoma?
When excessive gastric acid is leaked into the duodenum, the acids in the duodenum inactivates lipases and reduces absorption of fats from diet, resulting in fatty poops
T/F: gastrinomas could lead to constipation and fatty poop
False; yes it can lead to fatty poop (aka steatorrhea) but instead of constipation, it can lead to diarrhea because of impaired absorption of sodium and water in the duodenum
Sodium is absorbed in the duodenum via ________. What happens when there is increased acid in the duodenum?
Na/H antiporter
But when duodenum becomes more acidic due to gastric acid leakage to it, it impairs the absorption of sodium and water, promoting diarrhea
What happens when pH of duodenum decreases?
Inactivates lipases and impair digestion of absorption of fats
Results in steatorrhea and diarrhea
What is VIPoma?
Tumors that secrete Vasoactive intestinal polypeptide, originating in the pancreas but some may be from the intestine
What does vasoactive peptide regulate?
Intestinal epithelial cell secretion of electrolytes (Na, K, Cl),
Smooth muscle relaxation (including vascular smooth muscle and the lower esophageal sphincter)
Blood flow in the GI tract
Clinical signs of VIPoma?
Diarrhea, dehydration
Hypokalemia and hypercalcemia
Bone resorption
Vasodilation (flushing), hyperglycemia
Excess excretion of electrolytes and bone resorption, think: