The pancreatic juice is a transparent, isotonic fluid secreted by the pancreas. It has both endocrine and exocrine functions. The exocrine secretions contain digestive enzymes like amylase, lipase, and proteases that aid in digestion. Bicarbonate ions secreted in pancreatic juice neutralize the acidic chime from the stomach and provide an optimal pH for the enzymes. The secretions occur in three phases regulated by both the autonomic nervous system and hormones like secretin and cholecystokinin. Secretin increases the secretion of bicarbonate-rich fluid while cholecystokinin stimulates enzyme secretion after eating. Disorders like pancreatitis and cystic fibrosis can impair pancreatic function and digestion.

1. PANCREATIC JUICE
“E Group 18LM”
By: Sandeep Ganguani

2. PANCREATIC JUICE
 Transparent isotonic Fluid secreted from
pancreas
 Dual Nature: Secretions from both
Endocrine And Exocrine cells
 Daily Secretions: 1000-1500ml
 basal rate: 0.2-0.3ml/min, Stimulated
phase: 3ml/min
 pH: 8-9 Normal, slightly alkaline
Properties:

3. Endocrine Secretions:
 Harmones
Exocrine Secretions:
• Histologically resemble salivary
glands.
• Digestive Enzymes (secreted by
acinar cells)

4. Pancreatic Juices Secretory
Phases:
Three phases
1. Cephalic phase (20% secretions)
2. Gastric Phase (10% secretions)
 During cephalic and gastric phases secretion contains lesser quantity of
water, but sufficient solid compounds; so hardly reaches the Duodenum.
 cephalic and gastric phases are under control of ANS, ( Vagus nerve
through releasing Neurotransmitter AcetylCholine)
 Parasympathatic: increases secretions
 Sympathetic: decreases secretions.

5. 3. Intestinal phase:
 70% of secretions are released during this
phase.
 Intestinal phase of pancreatic secretions is
mostly under Harmonal control.
 Contains higher conc: of water and
Bicarbonate ions and rich in enzymes and
and other solids
 Physiological actions of pancreatic juice are
performed during this phase.

6. Composition:
1. 98-99% water
2. 1-2% Solids
 Solids, having both organic(1/3rd) and
inorganic(2/3) compounds.

7. Solids:
Inorganic Ions:
Major Ions:
1. Bicarbonate Ions
2. Na Ions
3. K Ions
4. Cl ions
Minor Ions:
1. Mg ions
2. Phasphorous

8. Bicarbonate Ions:
 Secreted by Duct epithelial cells.
 Secreted 5 times more that of plasma
 Functions:
1. Neutralise acidic pH of Chime coming from stomach.
2. Block Digestive Active substances of gastric juice.
3. Provide proper pH for functions of pancreatic enzymes.

9. Solids:
Organic:
 Mainly Enzymes: Amylase, Lipase,
Protease and trypsin inhabitor

10. Pancreatic α-Amylase:
 Active form, acts on polysaccharides (glycogen and
Starch).
 Hydrolyses α 1_4 glycosidic linkage of polysaccharide chain.
 Cofactor: Cl ions function as increasing the activity for
Pancreatic Amylase.
 Inhabitor: Gastrin Harmone
 Optimum pH: 7.1
Note:- pancreatic amylase differs from salivary amylase in
performance medium, Salivary amylase is most active on pH of
6.8

11. Proteases:
 Following enzymes, acting on proteins are found
in Pancreatic Juice:
1. Trypsin
2. Chymotrypsin
3. Carboxy_peptidases
4. Amino_peptidases
5. Elastases
6. Collagenase

12. Trypsin:
 Basically secreted in inactive form Trypsinogen.
 Enterokinase of duodenal secretion activates
Trypsinogen to trypsin.
 Trypsin thus activated by enterokinases,
activates other pancreatic enzymes.
 Hydrolyses proteins to proteoses and
polypeptidases.
 Functions as Blood Clotting activating
prothrombin to thrombin.
 pH: 8_9

13.  Chymotrypsin:
_Released as inactive form Chymotrypsin.
_Trypsin activates Chymotrypsin into trypsin.
_ Causes Milk coagulation
Note:- The main difference between
chymotrypsin and trypsin is the amino acids
they select for. Chymotrypsin is the enzyme
that selects for the aromatic amino acids:
phenylalanine, tryptophan, and
tyrosine. Trypsin is the enzyme that selects for
the basic amino acids: lysine and arginine.

14. Lipolytic Enzymes
1. Pancreatic Lipase
2. Cholestrol estrase
3. Phospholipase A2
4. Co-Lipase
5. Bile salt activated Lipase

15. Pancreatic Lipase:
 Act on fat globules after they are emulsified
 Major enzyme causes hydrolysis of tryglycerides
into monoglycerides and fatty acids.
 Activators: Bile salt, soaps, synthetic detergents
 Inactivated by acid enviornment
 pH: 8.2_9.2
 This is water soluble enzyme.

16. Regulation of Pancreatic Secretion_
Intestinal Phase
 Pancreatic secretions during intestinal phase are
mostly under Harmonal Control.
 Two major harmones basically control pancreatic
secretions:
1. Secretion
2. Cholesystokinin (CKK)

17. Regulation of Pancreatic Secretion_
Intestinal Phase
1. Secretin:
 secreted by S_cells of duodenal mucosa.
 stimulus: HCL of gastric juice coming with chyme.
 Increases secretion of watery alkaline solution from
pancreas (especially Bicarbonate ions)
 Increases the activity of CCK.

18. Regulation of Pancreatic Secretion_
Intestinal Phase
2. Cholecystokinin(CCK)
 Secreted from I cells of duodenal mucosa.
 Stimulus: diet of good proteins and fats
 stimulates secretion of pancreatic juice rich in enzymes
and lower water conc:
 Delays gastric emptying.
 Increases the action of Secretin.

19. Applied Aspects
 Acute Pancreatitis: acute inflammatory disease
due to autodigestion of pancreatic tissue by
proteolytic enzymes.
 Chronic Pancreatitis: Chronic inflammation
 Cystic Fibrosis: Decrease pancreatic enzyme
leads to Steatorrhoea.

20. 🔥Thank You 🔥