GI Physio Secretions (In class)- Karius Flashcards
what are in the primary saliva secretion?
amylase, ions, mucus
what can stimulate salivation?
tastes, smells, cortical stimuli (thought), gastric/duodenal irritation
neurotransmitter associated with salivation?
Ach
what are the secretions of the esophagus
mucus for lube and protection
gastric glands have what kind of cells?
mucus secreting cells, HCl/Intrinsic factor, enzyme precursors (pepsinogen)
pyloric glands have what kind of cells?
mucus secreting cells, gastrin production, pepsinogen
cardiac glands have?
mucus secreting cells
what are some of the cellular characteristics of parietal cells?
lots of mitochondria, high SA, lots of golgi
what stimulates pancreatic enzyme secretion?
Ach, Gastrin, CCK
what stimulates pancreatic bicarb secretion?
secretin
what occurs during the gastric phase of pancreatic secretion?
Ach and gastrin
what occurs during the intestinal phase of pancreatic secretion?
CCK and secretin, increase enzyme, and increase bicarb flow
what are the hepatic secretions?
waste products (cholesterol, bilirubin/heme), bile salts & phospholipids, water and electrolytes (duct cells and bicarb)
what is the purpose of adding phospholipids to secretions?
to increase the solubility of cholesterol
how are bile acids formed?
- cholesterol backbone
- primary bile acids, cholic acid, chenodeoxycholic acid
- converted to secondary acids by bacterial action
how are bile salts returned to hepatocytes?
enterohepatic circulation
hepatic water/bicarb secretions are controlled by?
secretin and bile salts
what is the function of the gallbladder?
stores bile, reabsorb water/electrolytes (concentrates for room)
what elicits contraction of the gallbladder?
CCK, vagus (weak)
What cause relaxation of the sphincter of Oddi?
CCK, peristalsis (esp. duodenal)
what is the stimulation for intestinal secretions?
tactile stimulation of mucosa
what are the 3 intestinal secretions?
mucus, bicarb/water, enzymes (but aren’t really secreted- bound to membrane of cells that have been sloughed off)
what causes mucus secretion in the colon?
tactile stim. & parasympathetic
bicarb secretion in colon is high due to?
need to neutralize acids from bacteria (not gastric)
what 2 ions are in high concentration in mouth?
bicarb and K+
