Histo Upper GI Tract Flashcards Preview

GI Midterm > Histo Upper GI Tract > Flashcards

Flashcards in Histo Upper GI Tract Deck (38):
1

mucosa

a lining epithelium w. mucosal and submucosal glands and ducts
an underlying lamina propria consisting of a vascularized loos connective tissue
a thin layer of smooth m, the muscularis mucosae

2

epithelium of oral cavity oropharynx esophagus anal canal

stratified squamous

3

epithelium of stomach SI LI rectum

simple columnar

4

epithelium function

selective permeable barrier
transport, digestion, absorption
hormone production

5

lamina propria

vascularized loose CT
lymphatic nodules and scattered immunocompetenent cells
in SI and LI is relevant site of immune response (peyers patch or GALT)

6

muscularis mucosae

thin double layer of smooth m
increases contact area with food
propel and mix food in GI tract

7

submucosa

dense irregular CT w/ large BV lymphatics and nn branching into the mucosa and muscularis
glands are present in esophagus and duodenum

8

mucosa

stomach and SI both mucosa and submucosa extend into the lumen as folds
mucosa alone can extend into the lumen as fingers
mucosal glands increase the secretory capacity
vili increase the absorptive capacity of the digestive tube
significant variations from segment to segment of the digestive tract

9

mucularis externa

circular layer - reduces the lumen
longitudinal layer - shortens the tube

10

adventitia

outside peritoneal cavity
binds to the body wall
loose CT
BV and nn

11

serosa

w/in peritoneal cavity
loose CT
simple squamous epithelium
BV, nn, adipose tissue

12

extrinsic (ANS)

sympathetic - decrease motility/secretions
parasympathetic - increase motility/secretions

13

intrinsic/enteric

distinct interconnected neuronal circuits
submucosal plexus (Meissner)
myenteris (Auerbach) - b/w inner and outer layers of muscularis externa
peristaltic contractions to move food bolus
secretory activity of mucosal/submucosal glands

14

esophagus mucosa

non keratinized stratified squamous epithelium
non absorptive and friction resistant

15

esophagus lamina propia

thin, elastic CT
upper muscularis mucosae contain elastic fibers

16

lower esophagus

contains smooth m fibers

17

esophageal glands

secrete a lubricating layer of mucus

18

muscularis propria or extrena of esophagus

thick
transitions from skeletal m to smooth m

19

clinical significance swallowing and dysphagia

UES - anatomically defined, cricothryroid
LES - functionally defined, gastroesophageal sphincter
GERD - change in epithelium to columnar

20

Barrett's esophagus

abnormal columnar epithelium replaces the stratifies squamous epithelium
predisposes to the development of adenocarcinoma of the esophagus

21

stomach

rugae
gastric glands/pits
protective layer of mucous protects surface epithelium

22

cardia region

simple tubular and coiled at the lower end
lined by mucus secreting cells

23

mucous cells

surface mucous cells lining the pit
mucous neck cells located at the opening of the gastric gland into pit
produce mucins, glycoprotiens
produce HCO3 to neutralize microenvironment

24

chief cells

lower 3rd of gastric gland
secret pepsinogen to digest proteins

25

parietal cells

fundus-body of stomach
secrete hydrochloric acids and intrinsic factor

26

autoimmune gastritis

autoantibodies to H/K dependent ATPase
destruction of parietal cells causes a reduction in HCl and lack of synthesis of intrinsic factor

27

helicobacter pylori

found in mucus blanket lining, pyloric antrum
presence has been associated w. acid peptic ulcers and adenocarcinoma of the stomach

28

gastoenteroendocrine cells

produce peptide hormones that work on the alimentary tube
regulation of water, electrolyte metabolism and enzyme secretion
regulation of gastrointestinal motility and mucosal growth
stimulation of the release of other peptide hormones

29

secretin

released by the duodenal glands of Lieberkuhn
stimulates pancreatic and duodenal to release bicarbonate and fluid release
w/ CCK stimulates the growth of exocrine pancreas
stimulates chief cells to secrete pepsinogen
inhibits gastrin release which reduces HCl

30

gastrin

produced by G cells in pyloric antrum
stimulate the production of hydrochloric acid by parietal cells
activate CCK to stimulate gallbladder contraction

31

CCK

stimulates gallbadder contraction and relaxation of the sphincer of oddi

32

glucose-depennent insulinotropic peptide

stimulates insulin release

33

motilin

released every 90 minutes during fasting
stimulates GI motility

34

ghrelin

produced in stomach fundus
leads to release of GH

35

pylorus

simple tubular and branched at very lower end
pits are deeper
mucus secreting cells

36

lamina propria of stomach

reticular and collage fibers

37

sumbucosa of stomach

dense irregular CT
submucosal plexus of Meissner

38

muscularis externa of stomach

circular
oblique
longitudinal