28.0 GI: MONOGASTRIC STOMACH
a) Define and use properly the following words: Cardiac stomach, Fundic stomach, Pyloric
stomach, Rugae, Gastric pits, Gastric glands, Chief cells, basophilic, pepsinogen,
intrinsic factor, Vitamin B12 absorption, Parietal cells, Acidophilic, HCl , Mucus neck
cells, Argentaffin cells, Neurotransmitter, Pyloric glands, Cardiac glands, Mucus.
b) Describe and associate basic structure/function for the following: all structures listed
above.
c) Identify by microscopy: Fundic stomach, Pyloric stomach, Rugae, Gastric pits, Gastric
glands, Chief cells, basophilic, Parietal cells, Acidophilic, Mucus neck cells, Argentaffin
cells, Pyloric glands, Cardiac glands, Mucus.
1
MONOGASTRIC STOMACH
I.
ANATOMY
1. Cardiac region
a. Located nearest the heart.
b. Esophagus connects to the stomach
2. Fundic Region
a. body of the stomach.
3. Pyloric Region
a. connects the stomach to the duodenum.
4. Mucosal membrane contains excessive folds called rugae
II.
GASTRIC PITS
1. Minute depressions of the mucosal surface
a. Occur throughout the stomach but varies in morphology in different region
2. Fundic region
a. small gastric pits
3. Pyloric region
a. deep gastric pits
4. Epithelium
a. Diagnostic feature
b. simple columnar similar to the surface of the stomach
i. They secrete mucus; appear washed
ii. The secretions coat the stomach to help prevent auto-digestion
III.
GASTRIC (FUNDIC) GLANDS
1. Three to seven gastric glands open into the bottom of a gastric pit
2. Gastric glands are long and straight and extend into the lamina propria
3. Four cell types
a. Chief cells
i. Most numerous cells in the fundic gland
ii. Morphology and staining appearance
1. square or pyramidal
2. basal nuclei
3. area above the nucleus is basophilic
4. most of the cytoplasm is pale staining
iii. Chief cells secrete pepsinogen
1. and intrinsic factor
2. is important for Vitamin B12 absorption
b. Parietal cells
i. Large cells that are spherical or oval shape
ii. Central nucleus
2
iii. Acidophilic cytoplasm
iv. Granular appearance due to the abundance of mitochondria
v. Function
1. make HCl
2. and intrinsic factor, which is important for Vitamin B12 absorption
c. Mucus neck cells
i. At origin of the fundic glands
ii. Not distinct histologically
d. Argentaffin cells
i. Require special stain to see
ii. Secrete neurotransmitter
III. Associated with some tumors
IV.
PYLORIC GLANDS
1. Below the gastric pits
2. Pale, washed out appearance
a. Mucus producing
b. Do not produce digestive enzymes or HCl
c. Different morphology than fundic
i. Small and convoluted
ii. numerous cross sections
V.
CARDIAC GLANDS
1. resembles pyloric glands
VI.
MUSCULARIS MUCOSA
1. Relatively thick
VII.
SUBMUCOSA AND MUSCULARIS EXTERNA
1. Submucosa; normal connective tissue constituents
2. Muscularis externa
a. 3 layers of smooth muscle
3