Guanylin and uroguanylin agonist Flashcards
What is linaclotide?
An agonist of the guanylyl cyclase receptor
Linaclotide is also known by the brand name Linzess.
What receptor does linaclotide bind to?
GC-C receptor
GC-C stands for guanylate cyclase-C.
What is the effect of linaclotide on intestinal fluid volume?
Increases intestinal fluid volume and bulks stool
What conditions is linaclotide used to treat?
Irritable bowel syndrome with constipation and chronic idiopathic constipation
When should linaclotide be taken?
On an empty stomach at least 30 minutes before the first meal
What effect does taking linaclotide after a high-fat breakfast have?
Results in looser stools and a higher stool frequency compared to fasting
What are common side effects of linaclotide?
Diarrhea, fecal incontinence, dehydration, electrolyte loss
Cl, HCO3, Na are pumped into lumen and flushed w/stool
What eletrolytes are lost with linaclotide (Linzess)?
Cl, HCO3, Na are pumped into lumen and flushed w/stool
What hormones are secreted by goblet cells in the colon?
following the ingestion of dietary salts
Guanylin and uroguanylin
small polypeptide paracrine hormones
What is the role of guanylin in the intestine?
Acts as an agonist of the guanylyl cyclase receptor GC-C
receptor that regulates electrolyte and water transport** into** the lumen of the intestine.
How does activation of the GC-C receptor affect cGMP levels?
Increases cGMP levels
What does activated cGMP do in the intestine?
Activates CFTR (cystic fibrosis transmembrane conductance regulator)
What ions are secreted into the lumen due to CFTR activation?
(cystic fibrosis transmembrane conductance regulator)
HCO3- and Cl- into the lumen
How does sodium follow in the intestinal lumen?
Passively follows the negative ionic gradient
What follows sodium in the intestinal lumen?
Water follows the osmotic gradient
What is the outcome of the processes initiated by guanylin in the intestine?
Increased intestinal fluid volume and accelerated transit
