Histology of the Oesophagus and Stomach Flashcards
Type of muscle in each 1/3 of the oesophagus
- Upper = striated (skeletal)
- Middle = mix
- Lower = smooth
Tissue layers of the oesophagus
- Stratified squamous epithelium
- Lamina propria
- Muscularis mucosa
- Submucosa
- Circular muscles
- Longitudinal muscle
What causes the star-shaped lumen of the oesophagus?
Contraction of the muscularis mucosa creating longitudinal mucosal folds
What glands are found in the oesophageal submucosa and what is their function?
- Submucosal (accessory salivary)
- Make secretion to lubricate mucosal surface
What is the epithelial change at the gastro-oesophageal junction?
Stratified squamous –> simple columnar
4 macroscopic regions of the stomach
- Cardia (surrounding oesophageal orifice (OO))
- Fundus (above horizontal line from OO)
- Body (below line)
- Pyloric antrum (surrounding pylorus)
3 histological regions of the stomach
- Cardiac region
- Pyloric region
- Fundic region
What glands are found in the fundic region of the stomach?
Fundic/gastric glands
Components of the gastric gland and their function
- Pit = entrance to gland
- Neck = where branching can occur
- Deep zone = where acid/enzyme/hormones are made
2 types of cell in the pit/neck of a gastric gland, and what they do
- Surface mucous cell (simple columnar)
- Neck mucous cell
- Secrete mucous
What does the gastric mucosa contain to give it its protective function?
Lots of HCO3-
3 types of cell in the deep zone of a gastric gland and their functions
- Parietal cells (secrete HCl + intrinsic factor)
- Chief cells (enzyme secretion)
- Enteroendocrine cells (secrete hormones)
What does intrinsic factor play a role in?
Absorption of vitamin B12
What cells are found in the isthmus (just above neck) of a gastric gland, and what is their function?
Undifferentiated stem cells (replace cells above or below)
Which cells dominate the cardiac and pyloric regions of the stomach?
Columnar mucous cells
