Alimentary 1: Esophagus and Stomach Flashcards
mucosa includes
- epithelial lining
- propria
- muscularis mucosa
what is located in the submucosa
- glands
- nerves
orientation of externa
- 2 layers of smooth muscle at right angles
- outer longitudinal
- inner circular
mucosal lining of the esophagus
- SSNKE
- lamina propria
- muscularis mucosae
submucosa of the esophagus
- loose CT
- esophogeal glands
muscularis externa of the esophagus
upper third=skeletal
middle third = mixed
lower third = smooth
-inner circular outer longitudinal
where is the adventitia of the esophagus located
-thorax
where is the serosa located
abdominal cavity
distinctive characteristic of the esophagus
-longitudinal muscularus mucosa
nerves from the submucosa plexus (meissners) go to
muscularus mucosa
secretions of the esophagus
bicarb
- mucins
- antimicrobials
- pepsinogen
- EGF
where does the esophagus enter the abdomen
-esophageal hiatus in the diaphragm
what is the narrowest portion of the digestive tract
esophagus
serosa
- this is on the visceral side of the hollow organ
- most of abdominal part
invaginations of the lamina propria
-these contain caps and nerve endings
what types of glands are found in the esophagus
serous and mucus
-mixed
gastroesophageal junction
-goes from SSNKE to simple solumnar in the stomach
barrett esophagus
- metaplasia occurs when acids from the stomach gets into the esophagus
- this is a protective function but in the end causes hard by the cell growth being uncontrolled
exocrine secretions of the stomach
- mucus
- HCl
- intrinsic factor
- pepsinogens/pepsins
- gastric lipase
- lysozyme
intrinsic factor
glycoprotein needed for absorption of vitamin B12
endocrine secretions of the stomach
-hormones: gastrin, ghrelin, and somatostatin
stomach mucosa
- simple columnar epithelium
- mucosal glands in the lamina propria surrounded by loose Ct
- muscularus mucosae has inner circular and outer longitudinal
submucosa of the stomach
- dense CT
- no glands
muscularis externa of the stomach
-inner oblique and outer longi
lower esophogeal sphincter
- inner circular muscle (clasp)
- oblique fibers at cardial notch this is a gastric sling
arrangement of pits and glands in the stomach
- cardial: short/short
- fundus/body: Short/long
- pyloric glands: long/short
cells found in the pits/glands of the fundic region
- pariteal cells in the middle
- chief cells toward the bottom
- enteroendocrine cells at the bottom
parietal cells
- secrete HCl
- secrete intrinsic factor (for VB12 absorption)
- active have white spaces where the cannuliculi have expanded
- have many mitochondria surrounding inner surface of plasma mem to produce ATP to secrete HCl
chief (zymogenic) cells
-secrete pepsinogen, lipase, chymosin
smooth muscle of the fundic stomach
-projects between the pits in order the allow the tissue to be squeezed and glanduar contents released
cells of the pyloric region
- mostly mucous
- enteroendocrine
H pylori
releases ammonia in order to neutralize its environment in the stomach
- once colonized, creates an inflammatory response
- surface components mimic those of the cell surface therefore Ab’s made against it will target stomach epithelial cells
gastritis
- acute
- chronic
- acute: mild, temproary, may be caused by agents that render the lining. epithelium sensitive to acid induced damage. could be due to alcohol or NSAIDs
- chronic: progressive, irreversible decay (atrophy) of the stomach mucosa. May be autoimmune in nature or caused by bacterial infection usually h pylori. may lead to pernicious anemia
enteroendocrine cells
- manny found in the glands
- secrete somatostatin, ghrelin, enterochromaffin
pyloric sphincter
-thickened inner circular muscle is what allows the lips of the sphincter to close
