GI HORMONES
This hormone, released from G cells in the stomach in response to gastric distention and peptides (notably phenylalanine and tryptophan), is also inhibited by somatostatin.
What is gastrin?
This cell secretes HCl and intrinsic factor.
What are parietal cells?
What is sodium?
This VFA is the primary substrate for gluconeogenesis.
What is propionate?
This metabolic pathway occurs in the liver when acetyl-CoA accumulates and oxaloacetate is depleted. Which hormone might we give which inhibits this process?
What is ketogenesis; and insulin
This hormone is the strongest stimulus for pancreatic enzyme secretion while also stimulating contraction of the gallbladder and inhibits gastric emptying.
What is cholecystokinin (CCK)?
This is secreted by chief cells in the fundus of the stomach and is converted to its active form at low pH.
What is pepsinogen?
This transporter is responsible for glucose uptake from the intestinal lumen into cells.
What is SGLT1.
This condition results from rapid fermentation of carbohydrates and decreased rumen pH. Bonus: what is the normal pH of a rumen?
What is ruminal acidosis. Normal is 5.5-6.8. If pH<5.0 motility is severely depressed.
This insulin-stimulated (and heparin-stimulated) enzyme hydrolyzes triglycerides from chylomicrons and VLDL, facilitating lipid clearance from the bloodstream and providing fatty acids for energy or storage.
This hormone is released in response to acid and fatty acids in the duodenum and stimulates bicarbonate secretion.
What is secretin?
Parietal cells secrete HCl into the lumen of the stomach and concurrently absorb __________. This reaction is catalyzed by ____________.
In the colon, passive diffusion via Na channels is most important. The Na channels of the colon are stimulated by this hormone.
What is aldosterone.
These, which are produced in the rumen epithelium or the liver, may provide energy to the CNS during prolonged periods of energy deprivation
What are ketone bodies.
Glucocorticoids ______ glucose uptake and metabolism in the peripheral tissues, particularly in the muscle and adipose cells.
What is decrease/inhibit.
What is glucose-dependent insulinotropic peptide (GIP)
Gastrin is released in response to eating a meal. It stimulates H+ secretion by interacting with the CCK2 receptor on parietal cells. What is the second messenger for gastrin on the parietal cells?
What is IP3 (inositol 1,4,5-trisphosphate) and Ca2+.
Vitamin b12 is absorbed in the _______ and requires __________.
What is ileum and intrinsic factor.
The reticular groove reflex may be stimulated by this hormone in adult animals.
ADH (vasopressin)
Beta cells in the pancreas produce insulin, alpha cells produce ______, D cells produce_________, F/PP cells produce ________.
What is glucagon, somatostatin, pancreatic polypeptide
Name 2 "candidate hormones" secreted by the cells of the GI tract and name an action
Motilin - increases GI motility
Pancreatic polypeptide - inhibits pancreatic secretions.
GLP-1 (glucagon-like peptide) - stimulates insulin secretion
Leptin - decreases appetite
Ghrelin - increases appetite
Name three drugs that block gastric H+ secretion, and where they work.
1) Atropine (blocks H+ secretion by inhibiting cholinergic muscarinic receptors on parietal cells, thereby inhibiting ACh stimulation of H+ secretion)
2) Cimetidine (blocks H2 receptors, inhibits histamine stimulation of H+ secretion)
3) Omeprazole (inhibits H+, K+-ATPase, and H+ secretion)
This structure allows lipids to be transported in the bloodstream after absorption
What are chylomicrons.
The _____ ______ nucleus of the brainstem houses the motility control center for the regulation of reticulorumenal motility.
What is dorsal vagal.
This hormone is produced with the goal of preventing postprandial hypoglycemia and main effect is at the liver. It leads to decreased glycogen synthesis and increased glycogenolysis and gluconeogenesis. Name the hormone and the intracellular second messenger it upregulates.
What is glucagon and cAMP