C:\Documents And Settings\User\Desktop\Stomach Histology

1. DIGESTIVE SYSTEM
Stomach Histology
Assoc. Prof. Dr. Karim Al-Jashamy
IMS/MSU2010

3. Stomach Anatomy:
•Openings
–Gastroesophageal
: To esophagus
–Pyloric: To
duodenum
•Regions
–Cardiac
–Fundus
–Body
–Pyloric

4. Regions of the Stomach

5. Layers of the Gastrointestinal Tract
•Mucosa
–Epithelium, CT, a little muscle
•Submucosa
–CT, glands
•Muscularis propria
–Muscles
•Serosa
–CT

6. Mucosa
Epithelium
Differs with location,
functions
Lamina propria
Loose CT, blood and
lymph vessels
Muscularismucosae
Thin layer with
smooth muscle

7. SUBMUCOSA
Loose/Dense irregular CT
Supports mucosa
Contains large blood vessels, nerves,
lymphatics
MUSCULARISPROPRIA
Two layers
Peristaltic contractions

8. SEROSA/ADVENTITIA
Loose CT
Major vessels, nerves,
adipose

9. The Stomach

11. Gastric Glands of Stomach

12. STOMACH x10
LP MM

13. GASTRIC
GLAND

14. Stomach
Sectionofthegastricglands
inthefundusofthe
stomach.
Notethesuperficial
mucus-secreting
epithelium.
Parietalcells(light-stained)
predominateinthemidand
upperregionsoftheglands;
chief(zymogenic)cells
(dark-stained)predominate
inthelowerregionofthe
gland.MM,muscularis
mucosae.

15. Histology LAYERS
1.Mucosa
• Thefirstmainlayer.
• consistsofanepithelium
(simple columnar
epithelium),thelamina
propriaunderneath,anda
thinlayerofsmoothmuscle
calledthemuscularis
mucosae
2.Submucosa
•Liesunderthemucosa
•Consistsoffibrous
connective tissue,
separatingthemucosa
fromthenextlayer.
•Thesubmucosalnerve
plexusisinthislayer.

16. 3.Muscularisexterna
•Consists of three
layers:
i.inner oblique layer
–responsible for creating the
motion that churns and physically
breaks down the food
i.middle circular layer
–constricted at the pylorus forming
pyloric sphincter, which controls
the movement of chymeinto the
duodenum
i.outer longitudinal layer
–Auerbach'splexus is found
between this layer and the
middle circular layer.

17. 4. Serosa
•outside the muscularis
externa
•consisting of layers of
connective tissue
continuous with the
peritoneum

18. Stomach Histology
•Gastric pits:
Openings for gastric
glands
–Contain cells
•Surface mucous:
Mucus
•Mucous neck:
Mucus
–Parietal:
Hydrochloric acid
and intrinsic factor
–Chief: Pepsinogen
–Endocrine:
Regulatory
hormones

19. •The gastric mucosa consists of surface
epithelium, gastric pits and gastric glands.
•The gastric glands extend from the
muscular mucosa extend into the stomach
lumen via gastric pits.
•The cells lining the surface and gastric
pits are identical throughout the stomach
•Glandsdiffer in different regions of the
stomach.
•Gastric pits occupy approximately 25%
of the mucosa. Pits lie parallel to one
another.
•There is more lamina propriaseparating
the pits than between the glands.
•In normal gastric biopsy degree ofpit
and glandular separation should be same
throughout the biopsy.
Normal Histological Features:

22. •Cardia-
Small area of predominantly
mucus secreting glands
surrounding the entrance of the
esophagus.
•The pits are shorter than the
antropyloric pits.
•Fundus andbody
Major histological region.
Consists of straight, tubular
glands.
Strands of muscularis
mucosae extend between the
glands from the base.
The glands secrete gastric
juices as well as protective
mucus.

23. •FUNDAL PART OF THE
STOMACH
Stained with
haematoxylin and eosin1 -
tunica mucosa
2 -tunica submucosa
3 -tunica muscularis propria
4 -tunica serosa
5 -epithelium of the mucosa
6 -lamina propria of the
mucosa (contains glands)
7 -muscularis mucosae

24. •Pylorus-
Branched glands open into
deep irregular shaped pits.
Composed of mucus
secreting cells.
•Mucus secreted by pyloric
glands lubricate and protect
entrance to the duodenum.
Scattered 'G' cells (endocrine
cells), secrete gastrin.
•Note:
Gastric mucosa forms a
barrier to diffuse of gastric
acid from the gastric lumen.

25. PYLORIC PART OF THE
STOMACH
Stained with
haematoxylin and eosin1
-tunica mucosa
2 -tunica submucosa
3 -tunica muscularis
propria
5 -lamina propria of the
mucosa
(contains glands)
7 -gastric pits in the
mucosa
8 -muscularis mucosae

26. Types of cells present in the stomach
•Mucous secreting cells (goblet
cells)-
–Line the luminal surface of the
stomach and gastric pits and gastric
glands.
–producemucus and bicarbonate.
•Mucous neck cells-
Present in the neck of the gland.
Produce mucin.
•Parietal cells (oxynticcells)
Distributed throughout the length of the gland,
but numerous in the middle portion.
Large, rounded cells with eosinophiliccytoplasm
and centrally located nucleus. Produce gastric acid.

27. •Chief cells (peptic or
zymogeniccells)
–Clustered at the base of the
gland.
–Identified by basally located
nuclei and strongly basophilic
granular cytoplasm.
Produce pepsinogen, digests
protein.

29. •Consists of a layer of
areolar tissue that
contains:
–blood vessels
–sensory nerve
endings
–lymphatic vessels
–smooth muscle cells
–scattered areas of
lymphoid tissue
The Lamina Propria

32. Assignment 1