Integrative review Flashcards
Myenteric nerve plexus
Receives input from lumenal mechanoreceptors Part of enteric nerve system Not going to stimulate secretion
How does hepatic vein differ from portal vein?
It has direct access to IVC
Portal vein, splenic vein, superior mesenteric vein, and inferior mesenteric vein all go through what before going to IVC?
Liver!
Vagus does not affect:
Salivation
Vagus does what in the GI?
-Stimulates gastric proton pump -Increases lower intestinal motility -Stimulates liver bile production -Relaxes sphincter of Oddi
Sympathetic input to foregut and midgut:
Greater, lesser, least splanchnic nerves
Sympathetic input to hindgut
Lumbar splanchnic
Main type of motility found in colon?
Segmental propulsion - not caused by circular muscle but caused by teniae coli -mass movement occurs as well, mass movement occurs over short bursts of time
Types of motility in small intestine:
Segmentation and peristalsis
Segmental propulsion vs. segmentation
Segmental propulsion caused by teneia coli
Branch of inferior mesenteric vein?
Left colic vein
Slow waves in the GI tract:
Resting membrane potential in the GI tract undulates in the GI tract, when you depolarize above -40 mV —> get spike potentials Depolarization occurs by parasympathetics
LES is controlled by
Enteric nerves
Ability of stomach to relax in response to food is
Vagal nerves
Greater splanchnic nerves
Foregut