GI General Principles Flashcards by Jacob Townsend

Retroperitoneal structures; mnemonic?

SAD PUCKER; suprarenal gland, aorta and IVC, duodenum (2,3,4), pancreas (except tail), ureters, colon (ascending and descending), kidneys, esopahgus, rectum

How well did you know this?

Not at all

Perfectly

Falciform ligament…connects?…contains?

Liver and abd wall…contains ligamentum ters hepatis (remnant of fetal umbilical vein)

How well did you know this?

Not at all

Perfectly

Heptoduodenal ligament…connects?…contains?

Liver and duodenum…Portal triad (common bile duct, portal vein, heptatic artery)

How well did you know this?

Not at all

Perfectly

Gastrohepatic ligament…connects?…contains?

Liver and less curvature of stomach…Gastric arteries…cut this to gain access to lesser sac during surgery

How well did you know this?

Not at all

Perfectly

Gastrocolic ligament…connects?…contains?

Greater curvture and transverse colon…gastroepiploic arteries

How well did you know this?

Not at all

Perfectly

Gastrosplenic ligament…connects? Contains?

Greater curvature and spleen…Gastric and gastroepiploic arteries

How well did you know this?

Not at all

Perfectly

Splenoreal ligament…connects….contains?

Spleen to posterio wall…splenic artery and vein and tail of pancreas

How well did you know this?

Not at all

Perfectly

Basal electric rhythm of stomac, duodenum and ileum

Stomach 3/min, duodenum 12/min => ileum 8-9/min

How well did you know this?

Not at all

Perfectly

Layers of gut wall (inside to outside)

MSMS - mucosa, submucoasa, msucularis externa, Serosa

How well did you know this?

Not at all

Perfectly

Mucosal layer…functions?…contains?

epithelium (think donut), lamina propria, muscularis mucosa…absorption, support, motility (resp.)

How well did you know this?

Not at all

Perfectly

Submucosa…functions?…contains?

Submusocal nerve plexus….Meissner’s plexus (parasympathetic) which innervates the muscuaris mucosa (for motility)

How well did you know this?

Not at all

Perfectly

Muscularis Externa….functions? Contains?

Myenteric nerve plexus aks Auerbach’s (sympathetic and parasympathetic) which controls GI tract motility

How well did you know this?

Not at all

Perfectly

Serosa…functions? Contians?

Support and can help connect to abd. Walls, etc. (aka adventitia

How well did you know this?

Not at all

Perfectly

Histology of Esophagus

Nonkeratinized squamous

How well did you know this?

Not at all

Perfectly

Histology of Stomach

Gastric glands

How well did you know this?

Not at all

Perfectly

Histo of duodenum

Villi and microvilli (for absorption), Brunner’s glands (secretes HCO3- and mucus), crypts of Lieberkuhn (secretes intestinal digestive enzymes)

How well did you know this?

Not at all

Perfectly

Hidto of jejunum

Plicae circulares (folds in mucosa) and crypts of Leiberkuhn

How well did you know this?

Not at all

Perfectly

Histology of ileum

Peyer’s Patches (in lamina prop and submucosa…which help with immunity …M-cells, with T-cells and B-cells…lymph nodes of the GI?), Plicae circulares, and crypts of Lieberkuhn…MOST GOBLET CELLS IN SMALL INTESTINE FOUND HERE

How well did you know this?

Not at all

Perfectly

Histo of colon

Crypts but no villi, lots of goblet cells

How well did you know this?

Not at all

Perfectly

Celiac Trunk….comes off of? Branches? Supplies? At the level of?

Abd. Aorta, main branhces are: splenic artery, left gastric (which also gives esophageal branch), common hepatic artery (which also gives hepatoduodenal artery; supplies: stomach, pancreas, spleen, proximal duodenum, gall bladder, liver; Level = T12

How well did you know this?

Not at all

Perfectly

SMA…Level? Supplies?

comes off below the celiac (at L1), distal duodenum up to 2/3 of transverse colon

How well did you know this?

Not at all

Perfectly

IMA…level? Supplies?

L3…supplies distal 1/3 of transverse colon down to upper rectum

How well did you know this?

Not at all

Perfectly

Anastamosis of the stomach blood supply?

Left and right gastric arteries; left and right gastroepiploic arteries…concept: collateral circulation occurs in the “pairs of arteries”: Superior epigastric with infereior epigastric, middle colic with left colic…superior rectal with middle and inferior rectal

How well did you know this?

Not at all

Perfectly

Three main portosystemic anastamoses

Esophagus (left gastric with esophageal veins), umbilical (paraumbilical with sup and inf epigastric), rectal (superior rectal with middle and inf rectal veins)

How well did you know this?

Not at all

Perfectly

Clinical signs of portal hypertension (anastamoses)

Esophageal varices (can lead to bleeding, hemoptysis), caput medusa (umbilical), INTERNAL hemorrhoids

Pectinate/dentate line...define?...differences in clinical?

Where endoderm becomes ectoderm near the anus...above line we get INTERNAL hemerrhoids and adenocarcinoma (not painful because it receives visceral innervation)...below line we get external hemeerhoids and squamouc cell carcinoma (painful because of pudendal)

Is the inner muscular layer circumferential or longitudinal?

Circumferential

Order of contents of the femoral triangle

Lateral to medial; nerve-artery-vein-lymphatics

Contents of femoral sheath

Vein and artery and lymph nodes; NOT the nerve

Gastrin source

G-cell of stomch antrum

Gasrin action

Increase gastric acid secretion (via ECL cells), increase gastric mucosa, increase motility

Gastrin regulation

Increas release due to stomach distention, alkalinization, amino acids, peptides, vagus nerve. Decrease due to acidic stomach pH.

What two aminoacids are potent stimulators of gastrin?

Phenylalanine and tryptophan

CCK source

I-cells of duodenum/jejunum

CCK action

Increase pancreatic protein secretion, increase gallbladder contraction, decrease gastric emptying, relaxes sphincter of Oddi

CCK regulation

Increased by fatty acids, amino acids

Secretin source

S cells of the duodenum

Secretin action

Increase pancreatic HCO3 secretion, decrease gastric acid secretion, increase bile (liquid) secretion

Secretin regulation

Increased by fatty acids and acid in lumen of duodenum

What pH do pancreatic enzymes work at ideally?

Basic

Somatostation source

D_cells (pancreatic islet,s GI mucosa)

Somatostatin action

Decrease gastric acid and pepsinogen secretion; decrease pancreatic and small intestine fluid secretion, decrease gallbaldder contraction and decrease insulin/glucagon release

Somatostation regulation

Increased by acidity and decrease by vagal stimulation

Glucose-dependent insulinotropic peptide (GIP) source

K-cells (duodenum, jejunum)

Glucose-dependent insulinotropic peptide (GIP) action

Exocrine: decrease gastric H+ secretion; endocrine: increase insulin release

Glucose-dependent insulinotropic peptide (GIP) regulation

Increased by fatty acids, amino acids, oral glucose (NOT INJECTED GLUCOSE)

Vasoactive intestinal polypeptide source

Parasympathetic ganglia

Vasoactive intestinal polypeptide action

Increase intestinal watre and electrolyte secretion, relaxation of smooth muscles and sphincters

Vasoactive intestinal polypeptide regulation

Increased by GI distention and vagal stimulation; decreased by adrenergic output

Nitric oxide effect on LES

Decreases tone; loss of NO is implicated in achalasia

Motilin source

Small intestine

Motilin action

Produces migrating motor complexes (MMCs)

Motilin regulation

Increases in fasting state

Intrinsic factor source

Parietal cells

Intrinsic factor action

Binds B12 in duodenum, uptake at terminal ileum

Gastric acid source

Parietla cells in gastric body

Gastric acid regulation

Increased by hiastmine, Ach, gastrin; lowered by somatostatin, GIP, prostaglandin, secretin

How does gastrin increase HCL (gastric acid)?

It is secreted into circulation and then hits ECL cells (Enterochromaffin-like cells) which then release histamine which signals pariental cells to secrete HCL and intrinsic factor

Pepsin source

Chief cells in gastric body

Pepsin regulation

Increased by vagal stimulation, local acid

What converts pepsinogen to pepsin?

Stomach acidity, then autocatalyzation

Normal saliva tonicity

Hypotonic

Effect of high flow rates on saliva tonicity

Isotonic

Saliva ionic composition

High bicarb, low K, increase in Cl and Na as flow rates increase, decrease K+

Pancreatic juice ionic composition

High Na, inverse relationshpi between HCO and Cl as flow rate increases, low K

How do vagal cells stimulate G-cells?

Via GRP, NOT Ach - muscarinic antaognists have no affect!

What ist he tonicity of pancreatic fluid?

Isotonic

Level of CL and HCO3 in pancreatic fluid with low and high flow

Low flow => high Cl, high flow => high HCO3

Enzyme composition of pancreatic secretions

amylase, lipase, phospholipase A, colipase; tryspin, chymotryspin, elastase, carboxypeptidase

Where is trypsinogen activated?

Brush border by enterokinase/enteropeptidase

Amylase hydrolyzes what bonds? Produces what sugar type?

Disaccharaides; maltose and alpha-limit dextras; hydroylyzes 1-4 alpha glycosidic linkages

Where is iron absorbed

Duodenum

Where is folate and B12 absorbed?

Folate - jejunum, B12 in Ileum with intrinsic factor

In what form are the carbs absorbed in the GI tract?...catalyzed by which enzyme and important of this step?

Borken down from oligosacc and Absorbed as monsacc. Or disacchrides...catalyzed by oligosaccharide hydrolase (it is the rate limiting step)

What transporter uptakes glucose from the GUT lumen

SGLT

What transporter moves glucose from gut epithelial cells to the blood

GLUT 2

What transporter uptakes fructose from the GUT lumen

GLUT 5

What does the D-xylose absorption test tell you?

Distinguiishes GI mucosal damage from other causes of malabsorption

Liver anatomy...Zone 1, 2, 3 conatins what?

1- Hepatic artery and portal vein (aka periportal zone...drains blood and it goes through the canniculi in Zone 2. Zone 3 has the central vein (that goes to systmic circulation and is now "clean"

Viral hepatitis affects which liver zone first?

Zone 1

Which liver zone is affected by ischemia first?

Zone 3

Which liver zone has P450 system and is sensitive to toxic injury the most?

Zone 3

Bilirubin metabolism...quick:

In macrophages: RBCs---> heme---> unconjugated bilirubin.....In blood: Uncong. Bilirubin binds with albumin...In Liver: *UDP glucuronosyl transferase* conjugates bilirubin...In gut: gut bacteria convert to urobilogen...80% goes to poop...20% goes back into circ and goes to pee

GI General Principles Flashcards

(83 cards)