GI Flashcards
rostral fold closure defect
sternal defect (ectopic cordis)
gastroschisis
abdominal contents through folds, not covered by anything
omphalocele
protrusion of abdominal contents, covered by peritoneum
jejunal and ileal atresia
from disruption of mesenteric vessels - ischemic necrosis - segmental resorption
exposure risk in hypertrophic pyloric stenosis
macrolides
ventral pancreatic buds form
uncinate process and main pancreatic duct
dorsal pancreatic bud forms…
body, tail, isthmus, and accessory duct
spleen embryonic origin…
mesentery of stomach, has foregut supply
retroperitoneal structures
Suprarenal glands Aorta Duodenum Pancreas Ureters Colon (descending/ascending) Kidneys Esophagus Rectum
falciform ligament
connects liver to anterior abdominal wall
- contains ligamentum teres hepatis (remnants of umbilical vein)
hepatoduodenal ligament
connects liver to duodenum
- contains portal triad
gastrohepatic ligament
connects liver to lesser curvature of stomach
- contains gastric arteries
layers of gut wall
mucosa - epithelium, lamina propria, muscularis mucosa
submucosa - contains Meissner
muscularis externa - myenteric (Auerbach plexus)
serosa or adventitia
erosions
mucosa only
brunner glands
secrete bicarb in duodenum
paneth cells
in duodenum, secrete defensins and lysozymes and TNF
plicae circulares
mostly in jejunum
histology of colon
abundant goblet cells
what causes SMA syndrome
decrease in mesenteric fat (low body weight and poor nutrition) - blockage of third part of duodenum
parasympathetic innervation of gut
first 2/3 = vagus
last 1/3 = pelvic
branches of celiac artery
left gastric, common hepatic, splenic
posterior duodenal ulcers penetrate…
gastroduodenal artery
three veins involved in portal HTN
- left gastric to azygous
- paraumbilical to epigastric
- superior rectal to middle/inferior rectal
TIPS
shunt blood from portal vein to hepatic vein
venous drainage from above anal pectinate line
superior rectal vein to inferior mesenteric to splenic to portal (can cause internal hemorroids
arterial supply from anus above pectinate line
superior rectal artery
location of anal fissures
posterior - poorly perfused
hepatic stellate cells
store vitamin A and product ECM
things affecting liver zone 1
- viral hepatitis
- ingested toxins
things affecting liver zone II
yellow fever
things affecting liver zone III
ischemia
p450
metabolic toxins
alcoholic hepatitis
mnemonic for remembering spermaticord
ICE tie
- internal spermatic fascia - transversalis fascia
- cremasteric muscle and fascia - internal oblique
- external fascia - external oblique
indirect inguinal hernia
lateral to inferior epigastric arteries, failure of processus vaginalis to close
direct inguinal hernia
through hasselbachs triangle - medial to inferior epigastric arteries, lateral to rectus abdominis
hesselbach triangle
inferior epigastric arteries, rectus abdominis, inguinal ligament
gastrin
- secreted by G cells
- increased H+ and stomach motility
- release from GRP, stomach distension, contents, decrease with high acid
- large increase in Zollinger-Ellison syndrome
somatostatin
- secreted by D cells in pancreas
- decreases secretion of everything
- secreted with high acid and low vagal stimulation
- octreotide = analog
octreotide
analog of somatostatin
CCK
- secreted by I cells in small bowel
- increase in pancreatic secretion, gallbladder contraction, oddi relaxation
- secreted b/c fatty acid and amino acids
- acts on muscarinic pathways
secretin
- secreted by S cells in duodenum
- increases pancreatic bicarb, decrease stomach acid, increased bile secretion
- caused by acid in lumen of duodenum
- allows enzymes to function
GIP (glucose dependent insulinotropic peptide)
- K cells in duodenum
- decreases H secretion and increases insulin release
- increased by acids and glucose
- oral glucose leads to higher insulin because of this
VIP
- leads to relaxation of smooth muscles and sphincters
- increase in intestinal water and electrolyte secretion
NO
relaxation of LES, implicated in achalasia
ghrelin
hunger hormone, increased in Prader-Willi, decreased in gastric bypass
intrinsic factor
secreted by parietal cells, leads to B12 absorption in terminal ileum
pepsin
secreted by chief cells in stomach, starts protein digestion
low vs high flow of pancreas
low = high Cl- high = high bicarb
glucose and fructose absorption
glucose - SGLT1 (Na dependent)
fructose - facilitated diffusion by GLUT2
iron is absorbed in…
duodenum
folate is absorbed in…
small bowel
b12 is absorbed in…
terminal ileum, along with bile salts
menetrier disease
hyperplasia of gastric mucosa, hypertrophied rugae, too much mucus, parietal cell atrophy with less acid production
- precancerous
