3. Introduction:
The Pancreas(Pan= all; -creas= flesh) is an exocrine
gland of the digestive system as well as a hormone
producing endocrine gland.
The pancreas is a soft, a retroperitoneal gland
- (12-15cm) long
- 2.5cm thick.
It lies posterior to the greater curvature of the
stomach.
4. Parts:
The pancreas is divided
into four (4)
anatomical parts:
1. Head.
2. Neck.
3. Body.
4. Tail.
The head -expanded
portion.
Tail- tapering.
5. Anatomy:
The pancreas contains
a number of lobules
called “acini”
In between the acini
there are group of
endocrine cells called
“islet of langerhans”
The small ducts emerge
from these lobules &
unite & reunite to form
“pancreatic duct(duct
of wirsung)
6. The pancreas is
connected to
duodenum by two ducts:
1. Duct of Santorini.
2. Hepatopancreatic
ampulla (Ampulla of
vater)
7.
8. Secretions:
The Secretions of pancreas can be classified into:
1. Exocrine secretion. 2. Endocrine secretion.
1. Exocrine secretion: It is pancreatic juice which is digestive
in function. It is conveyed to duodenum through
pancreatic duct. Pancreatic juice contains the following
digestive enzymes:
i) Lipase: fats fatty acids & glycerol.
ii) Amylase: starch maltose.
iii) Trypsin: peptones amino acids.
In addition to the lipase,amylase & trypsin the
pancreas produces a host of other digestive
enzymes, including ribonuclease,
deoxyribonuclease, gelatinase and elastase
9. 2. Endocrine secretion: It is secreted by the islets of
langerhans & directly poured into the circulation.
This secretion contains two different hormones which
are secreted by two different cells of islet of langerhans.
These hormones are:
i) Glucagon : secreted by alpha cells.
- prevent blood glucose levels dropping too low.
To do this, it acts on the liver in several ways: It
stimulates the conversion of stored glycogen (stored
in the liver) to glucose, which can be released into the
bloodstream.
10. ii) Insulin: secreted by beta cells
- helps control blood glucose levels by signaling the
liver and muscle and fat cells to take in glucose from
the blood.
Insulin therefore helps cells to take in glucose to be
used for energy.
If the body has sufficient energy, insulin signals the
liver to take up glucose and store it as “glycogen.”
11. Bicarbonate and Water:
Epithelial cells in pancreatic ducts are the source of the
bicarbonate and water secreted by the pancreas.
Bicarbonate is a base and critical to neutralizing the
acid coming into the small intestine from the stomach.
In pancreatic duct cells, the bicarbonate is secreted
into the lumen of the duct and hence into pancreatic
juice.
