Transcript Biliary and Pancreatic Anatomy

Biliary and Pancreatic Anatomy
Liver
Gallbladder
Common bile duct
Pancreas
Pancreatic duct
Duodenum
Pancreatic Anatomy
Islet cell
secreting
hormones
Insulin and
glucagon
Blood
Cells secreting
pancretic juice
Duodenum
Pancreas
Pancretic
duct
Common bile duct
Pancreatic Secretions
Cell Type
Component
Function:
• Acinar
Enzymes
Digestion
• Ductal
HCO3 and Water
Protection
Digestion
PANCREATIC ACINAR CELL
ATP
Secretin
Adenyl cyclase
Ach
IP3
Ca2+
stores
?
Ca2+
?
CCK
Primary Stimulus
The Hormones also Modulate Enzyme Expression
Enzymes
cAMP
Pancreatic Duct Cell
Ca2+
CCK
Regulators of Pancreatic Secretion
Cell Type
• Acinar
PrimaryActivator
Potentiator
CCK / Ach
Secretin
(Ca2+ )
• Ductal
Secretin
(cAMP )
Cephalic and Gastric: Neural – Ach
Intestinal : Hormonal
CCK / Ach
Liver
Hepatic
Ducts
Right
Left
Common Bile
Duct
Pancreatic
Duct
Cystic Duct
Gallbladder
Ampulla
of
Vater
Sphincter
of Oddi
Duodenal
Lumen
• Excretory Component
- Bilirubin, Drug Metabolites.
• Secretory Component
- Bile: Produced and Filtered by Hepatocytes
Primary Bile Acids: Cholic Acid,
Chenodeoxycholic Acid
- Secondary Bile Acids
- Formed by Bacteria in the Intestine
: Deoxycholic Acid, Lithocholic Acid
Bile Acids
Primary bile acids
Fraction of Total
Secondary bile acids
80%
20%
Cholic acid
Deoxycholic acid
Cholesterol
Cholesterol
7-hydroxylase
Amphipathic
Carboxylic Acids
Chenodeoxycholic
acid
Liver
Lithocholic acid
Intestine
Bile Acids are Amphipathic
Have both Hydrophilic and Hydrophobic domains
Formation
Co-Lipase
of
Micelles
C
Hepatic cell plate
Bile canaliculus
Central
vein
Kupffer cell
Venous sinusoid
Terminal
bile duct
Portal venule
To Systemic
Circulation
Aorta
LIVER
HEPATIC
Celiac
(700)
(200)
STOMACH
SPLEEN
Portal (1800)
Vein mls/min
PANCREAS
Superior
Mesenteric
(700)
SMALL
INTESTINE
COLON
Inferior
Mesenteri
c
(400)
Rates:
ml/min
Enterohepatic
Circulation Liver
Cholesterol
7-hydroxylase
Cholesterol
Newly synthesized
bile acids
(0.6 g/24 h)
Portal
vein
Excreted
bile acids
(0.6 g/24 h)
2-4g
bile-acid pool
: circulated 6 - 10
times in 24 h
Colon
Bile
ducts
Stomach
Small intestine
SECRETIONS of the INTESTINES
Information pertaining to the next 3
slides is found in the Lecture Notes for
the last Lecture
Cell Loss
Villous
epithelium
Blood vessels
Lymph vessels
Nerves
Smooth muscle
Connective tissue
lymphocytes
Plasma cells
Eosinophiles
Absorptive cells
Goblet
cells
Muscularis
mucosa
Endocrine cells
Crypt
lumen
Undifferentiated
Goblet
Mitoses
Endocrine cells
Crypt
epithelium
Secretions of the Small Intestine (2000 ml/day)
• Crypts of Lieberkuhn: Small and Large Intestine
- Contain Primarily Epithelial Cells, Mucus Goblet
Cells, and Endocrine Cells.
- Water Secretion - VIP Activates Water Secretion
by Elevating cAMP and Cl- conductance.
- Cell Growth and Differentiation: Cell Turnover
at the Tip of a Villus is High (3-6 day Cycle).
Crypt Secretion
Cl-
Na+
cAMP
PDte
Cl-
? Ca2+
3 Na+
ATP
ADP
+ Pi
2 K+
H2O
Key Players:
cAMP Activated
Cl-
Channel
Na+ / K+ / Cl- Co-transport
Na-K ATPase
Na+ - K+
2 Cl
VIP – neurotransmitter
Histamine also can activate