GI II Flashcards
submucosa
dense irregular CT
glands in esophagus and duodenum
submucosal (meissner’s) nerve plexus
Meissners plexus
between circular muscle layer and muscularis mucosae
regulate secretory cells
regulate blood flow within walls of GI tube
innervates muscularis mucosae
Myenteric plexus (auerbach’s)
between longitudinal and circular muscle layers
regulate peristalisis
Both plexuses contain _____ neurons
autonomic
Muscularis mucosae of esophagus
ill-defined in proximal end
much more developed in distal end of esophagus
muscularis externa in esophagus
mostly adventitia in esophagus
distal end as it enters abdominal cavity will be serosa
Esophageal cardiac glands
found within the lamina propria
Upper 5% of esophagus contains _____ muscle
striated
> 50% of distal esophagus is ______ muscle
smooth
In between upper and distal esophagus contains _____ and ______ muscle
striated
smooth
_______ is present in thoracic esophagus
adventitia
Z line
dividing line between esophagus and stomach
is a sharp transition
Barrett’s esophagus
abnormal extension of stomach lining into esophagus
metaplasia is present
pt likely to develop cancer
How do you confirm barrett’s esophagus, and what type of stain would you use?
goblet cells must be present along with columnar cells
Alcian/PAS stain
What third of esophagus is mostly likely to harbor an adenocarcinoma
distal third
Deeper the cancer penetrates outward through the wall the ______ the stage
greater
HGD
high grade dysplasia
normal cell lining the esophagus with an abnormal growth
initial stage
within in the mucosa
Higher the stage, prognosis goes _____
down
Lymph and mestastatic cells flow more readily in the ______ _____ channels
submucosal lymphatic
Where are the lymphatic channels more abundant?
submucosa of the esophagus
How are lymphatic channels oriented?
longitudinally
allows mesastatic cells to spread far cranially or caudally
If lymphatics in the upper 2/3 of the esophagus are receiving cancer cells, how will they spread? And what lymph nodes will this impact?
cranially
lymph nodes of the neck
If lymphatics in the lower 1/3 of esophagus are receiving how will they spread? And what lymph nodes will this impact?
caudally
cardiac lymph nodes
gastric pits
invaginations of the epithelium and into the lamina propria
layers of muscularis externa (innermost to outermost)
olique smooth muscle
circular smooth muscler
longitudinal smooth muscle
3 types of glands in the stomach
cardiac glands
pyloric gands
gastric or fundic glands
Where are cardiac glands found
in the cardiac region
where are pyloric glands found
pylorus region
Where are gastric or fundic glands found
anywhere in between the cardiac and pylorus region
Gastric glands
most organized of the 3
Isthmus
glandular portion starts here and goes inferiorly
stem cell niche
What do parietal cells secrete?
HCl and intrinsic factor
Where is the main cell type in the neck
parietal cells
what is the function of intrinsic factor
important for absorbing B12 in distal GI tube
What are the acidophilic cell seen in the neck
parietal cells
What are the dark stained cells in the neck
chief cells
What is the main cell type in the fundus
chief cells
What is the function of chief cells
secrete pepsinogen
Cardiac glands
deeper into the lamina propria
irregular arrangement
What is the function of G cells
secrete gastrin
What type of ions are found in mucous. And is it acidic or alkaline?
bicarbonate
alkaline
Erosion
ulcer is confined to the mucosal layer, has not penetrated into the submucosa
Pyloric spinchter
junction between the stomach and duodenum
Esophagus and duodenum are two segments of the GI tube that will harbor ____ units
glandular
Plyoric sphiner is the thickening of what
muscularis externa
What layers does the pyloric spinchter have?
inner circle layer and outer longitudinal layer
Pilicae circulares
permanent folds of mucosa and submucosa largest modification slow movement of chyme increase the time available for enzymatic degradation of nutrients and their subsequent absorption increase surface area 3 fold
How is fat absorbed
through lymphatics that exist in the villi
Villus
fold of mucosa
has goblet cells interspersed amound columnar cells
core is lamina propria
increases surface area 10 fold
MIcrovilli
along apical domain of columnar cells
form brush or striated border
increase surface area 20 fold
told increase in surface area
600 fold
4 signature histologic features of gluten enteropathy (celiac sprue)
enterocytes disarrayed
villus atrophy
crypt (intestinal gland) hyperplasia
inflammation of lamina propria
Zollinger-Ellison syndrome
tumor of gastrin-producing cells
has gastrinoma
more robust rugae
increased acid production
gastrinoma
large number of gastrin producing cells
90% of gastrinomas are located where
within the gastrinoma or passaro’s triangle
What are the points of gastrinoma (passaro’s) triangle
junction of cystic and common hepatic ducts
junction of parts 2 and 3 of duodenum
point of the triangle is junction of pancreatic head and neck
