*Thi
Tabular note by: Preclinical Student of Faculty of Medicine, National University of Malaysia (UKM)
HISTOLOGY OF GIT & HEPATOBILIARY SYSTEM etc…
GENERAL ORGANISATION OF GIT (B) ENTERIC NERVOUS SYSTEM (C) MUCOSA-ASSOCIATED
- 4 Layers: Mucosa, Submucosa, Muscularis externa & Postganglionic sympathetic Postganglionic parasympathetic Injury or abnormalities (MA
Serosa/Adventitia fibres & ganglia fibres (Vagus nerve, CN X) Hirschsprung disease (congenital Chagas disease (American ▪ Lymphoid follicles: scattered
'
- Enteric Nervous System to ganglionic megacolon) trypanosomiasis) - May expand into submucosa
- Mucosa-associated Lymphatic Tissues (MALT) Enteric nervous system is severely - Source of lymphocytes involv
GIT ORGANS ACESSORY ORGANS OF injured → GIT motility disturbance ▪ Peyer’s patches: Aggregates
(GIT MAIN) GIT → dilatation of GIT ileum
(GIT-ASSOCIATED)
Oral cavity, oesophagus, Salivary glands, pancreas, liver
stomach, small & large & gallbladder
intestines, rectum & anus
(A) 4 LAYERS OF GIT GIT MAIN ORGANS:
REGIONS MUCOSA SUBMUCOSA MUS
beefy red
layer 1) OESOPHAGUS ▪ Non-keratinized stratified squamous ▪ Oesophageal glands (tubuloacinar PROXIMAL
Function: Convey food from epithelium glands) lumen helping in 1/3
yytne
.
oropharynx to stomach - Folded in relaxed state - Mainly mucous-secreting cells Skeletal
- To lubricate the passage of food muscles
1) MUCOSA (innermost layer)
▪ Modified according to their function
- Facilitate the transport & digestion of food → for absorption
- Provide a selective permeable barrier between luminal content & tissues
- Secrete hormones ( act in paracrine naturel
↳ affect neighbouring cells
thinner than
muscular"
2) STOMACH ▪ Simple columnar mucus-secreting Connective tissues, adipose tissue, OUTER
externa
epithelium blood, and lymph vessels
(a) EPITHELIAL LINING (b) LAMINA PROPRIA ✓
(c) MUSCULARIS MUCOSAE Function: mechanical & chemical
breakdown of food into chyme
leading
▪ Gastric pits: invagination of surface
Longitudina
of
+
Adapted to the function of a particular part of the GIT → 2 *- Loose connective tissue - Thin inner circular & outer epithelium to lamina propria
Stratified squamous
types
g)
increase surface area for
absorption
Columnar epithelium
- Rich in*smooth muscles,
blood & lymph vessels
longitudinal smooth muscles
- Between mucosa and submucosa
▪ Gastric glands: long simple/
branched tubular glands
BE riproduaeid
epithelium ✓ microvilli ✗ microvilli - Contain glands & - Extend deep into lamina propria
new cells are replenished ✗ ONLY lymphoid follicles - Synthesize & secrete gastric juice
by basal
layer → - 3 parts: Isthmus, body & base \ produce pepsin
Check region )
from - 5 cell types: Parietal (oxyntic), chief
of
abrasion (peptic/zymogenic), mucous neck, stem &
the
movement
of the ) toe '0MM " "
( Vmiirovilli
neuroendocrine cells
food
downwards Abrupt change of the epithelial lining occurs at: (junctions) gastroesophageal
junction
stomach -
stomach duodenum (
- Gastro-oesophageal 0
- Gastroduodenal
- IleocaecalClearing, 'T goblet
cells
g.
- Rectoanal squamous
GASTRIC GLANDS :
> T epi
simple
simple columnar epi .
lpiinkl
2) SUBMUCOSA
(a) LOOSE CONNECTIVE TISSUE (b) SUBMUCOSAL (MEISSNER’S)
NERVE PLEXUS
[
'
( purple
- Rich in*collagen fibres, blood & lymph
vessels contraction of ±
#
&
""
- Contain*adipose tissue, glands & musiuiarismul 3) SMALL INTESTINE • Simple columnar epithelium (enterocytes with ▪ Brunner’s glands: coiled tubular INTERN
Functions: neutralize gastric acid & brush border & goblet cells) submucosal glands in duodenum
lymphoid follicles
▪ Plicae circulares (PC)/Kerckring’s valve: - Alkaline secretions: protect Circu
pepsin, food digestion, nutrient - permanent folds (mucosa & submucosa) duodenal mucosa from gastric juice
Monty upper 4} of crew are striated muscle layers absorption, endocrine secretion - most prominent in jejunum & provide optimum pH for
3) MUSCULARIS EXTERNA + ▪ Intestinal villi: lamina propria (core) pancreatic enzymes
✓
control *
(a) SMOOTH MUSCLES (Striated muscle layers (b) MYENTERIC with lacteal, blood vessels & smooth - Lysozyme, epidermal growth
contraction
found in upper 2/3 of oesophagus) (AUERBACH’S) NERVE muscles factor
PLEXUS ▪ Crypts of Lieberkuhn: intestinal glands ▪ Peyer’s patches: aggregates of
Inner layer Outer layer tecontuin :
between bases of villi lymphoid nodules (distal ileum)
Tabular note by: Preclinical Student of Faculty of Medicine, National University of Malaysia (UKM)
HISTOLOGY OF GIT & HEPATOBILIARY SYSTEM etc…
GENERAL ORGANISATION OF GIT (B) ENTERIC NERVOUS SYSTEM (C) MUCOSA-ASSOCIATED
- 4 Layers: Mucosa, Submucosa, Muscularis externa & Postganglionic sympathetic Postganglionic parasympathetic Injury or abnormalities (MA
Serosa/Adventitia fibres & ganglia fibres (Vagus nerve, CN X) Hirschsprung disease (congenital Chagas disease (American ▪ Lymphoid follicles: scattered
'
- Enteric Nervous System to ganglionic megacolon) trypanosomiasis) - May expand into submucosa
- Mucosa-associated Lymphatic Tissues (MALT) Enteric nervous system is severely - Source of lymphocytes involv
GIT ORGANS ACESSORY ORGANS OF injured → GIT motility disturbance ▪ Peyer’s patches: Aggregates
(GIT MAIN) GIT → dilatation of GIT ileum
(GIT-ASSOCIATED)
Oral cavity, oesophagus, Salivary glands, pancreas, liver
stomach, small & large & gallbladder
intestines, rectum & anus
(A) 4 LAYERS OF GIT GIT MAIN ORGANS:
REGIONS MUCOSA SUBMUCOSA MUS
beefy red
layer 1) OESOPHAGUS ▪ Non-keratinized stratified squamous ▪ Oesophageal glands (tubuloacinar PROXIMAL
Function: Convey food from epithelium glands) lumen helping in 1/3
yytne
.
oropharynx to stomach - Folded in relaxed state - Mainly mucous-secreting cells Skeletal
- To lubricate the passage of food muscles
1) MUCOSA (innermost layer)
▪ Modified according to their function
- Facilitate the transport & digestion of food → for absorption
- Provide a selective permeable barrier between luminal content & tissues
- Secrete hormones ( act in paracrine naturel
↳ affect neighbouring cells
thinner than
muscular"
2) STOMACH ▪ Simple columnar mucus-secreting Connective tissues, adipose tissue, OUTER
externa
epithelium blood, and lymph vessels
(a) EPITHELIAL LINING (b) LAMINA PROPRIA ✓
(c) MUSCULARIS MUCOSAE Function: mechanical & chemical
breakdown of food into chyme
leading
▪ Gastric pits: invagination of surface
Longitudina
of
+
Adapted to the function of a particular part of the GIT → 2 *- Loose connective tissue - Thin inner circular & outer epithelium to lamina propria
Stratified squamous
types
g)
increase surface area for
absorption
Columnar epithelium
- Rich in*smooth muscles,
blood & lymph vessels
longitudinal smooth muscles
- Between mucosa and submucosa
▪ Gastric glands: long simple/
branched tubular glands
BE riproduaeid
epithelium ✓ microvilli ✗ microvilli - Contain glands & - Extend deep into lamina propria
new cells are replenished ✗ ONLY lymphoid follicles - Synthesize & secrete gastric juice
by basal
layer → - 3 parts: Isthmus, body & base \ produce pepsin
Check region )
from - 5 cell types: Parietal (oxyntic), chief
of
abrasion (peptic/zymogenic), mucous neck, stem &
the
movement
of the ) toe '0MM " "
( Vmiirovilli
neuroendocrine cells
food
downwards Abrupt change of the epithelial lining occurs at: (junctions) gastroesophageal
junction
stomach -
stomach duodenum (
- Gastro-oesophageal 0
- Gastroduodenal
- IleocaecalClearing, 'T goblet
cells
g.
- Rectoanal squamous
GASTRIC GLANDS :
> T epi
simple
simple columnar epi .
lpiinkl
2) SUBMUCOSA
(a) LOOSE CONNECTIVE TISSUE (b) SUBMUCOSAL (MEISSNER’S)
NERVE PLEXUS
[
'
( purple
- Rich in*collagen fibres, blood & lymph
vessels contraction of ±
#
&
""
- Contain*adipose tissue, glands & musiuiarismul 3) SMALL INTESTINE • Simple columnar epithelium (enterocytes with ▪ Brunner’s glands: coiled tubular INTERN
Functions: neutralize gastric acid & brush border & goblet cells) submucosal glands in duodenum
lymphoid follicles
▪ Plicae circulares (PC)/Kerckring’s valve: - Alkaline secretions: protect Circu
pepsin, food digestion, nutrient - permanent folds (mucosa & submucosa) duodenal mucosa from gastric juice
Monty upper 4} of crew are striated muscle layers absorption, endocrine secretion - most prominent in jejunum & provide optimum pH for
3) MUSCULARIS EXTERNA + ▪ Intestinal villi: lamina propria (core) pancreatic enzymes
✓
control *
(a) SMOOTH MUSCLES (Striated muscle layers (b) MYENTERIC with lacteal, blood vessels & smooth - Lysozyme, epidermal growth
contraction
found in upper 2/3 of oesophagus) (AUERBACH’S) NERVE muscles factor
PLEXUS ▪ Crypts of Lieberkuhn: intestinal glands ▪ Peyer’s patches: aggregates of
Inner layer Outer layer tecontuin :
between bases of villi lymphoid nodules (distal ileum)
