Transcript Pancreas gland

Pancreas gland
Definition

The pancreas is a
glandular organ that
secretes digestive
enzymes and hormones.
In humans, the pancreas
is a yellowish organ and
about the size of a hand
Location

The pancreas is a
gland located deep in
the abdomen between
the stomach and the
spine (backbone). The
liver, intestine, and
other organs surround
the pancreas.
Hormones of pancreas
pancreas has two types of secretion :
1 – endocrine hormone .
2 – exocrine enzyme .
The Endocrine Pancreas
.
Approximately 5 percent of the total
pancreatic mass is comprised of
endocrine cells. These endocrine cells
are clustered in groups within the
pancreas which look like little islands of
cells when examined under a
microscope. This appearance led to
these groups of pancreatic endocrine
cells being called "Pancreatic Islets“ or
“islets of langerhans”. Within pancreatic
islets are cells which make specific
pancreatic endocrine hormones, of
which there are only a few (the most
famous of course being insulin). These
cells within the islets are called
"Pancreatic Islet Cells".
Pancreatic Islet Cells secretion
The islets are endocrine tissue containing
four types of cells. In order of abundance,
they are the:
 beta cells, which secrete insulin and
amylin;
 alpha cells, which secrete glucagon;
 delta cells, which secrete somatostatin,
and
 gamma cells, which secrete a
polypeptide of unknown function
Pancreatic Endocrine Hormones
and Their Purpose
A - Insulin
Purpose: Regulate blood glucose (sugar) in the
normal range
Action: Forces many cells of the body to absorb and
use glucose thereby decreasing blood sugar levels
Secreted in response to: High blood glucose
Secretion inhibited by: Low blood glucose
Disease due to deficient action: Diabetes (large
section of Endocrine Web is devoted to Diabetes).
Disease due to excess action: Hypoglycemia
Pancreatic Endocrine Hormones
and Their Purpose
B - Glucagon
Purpose: Assist insulin in regulating blood glucose
(sugar) in the normal range (actions are opposite of
insulin)
Action: Forces many cells of the body to release (or
produce) glucose (increasing blood sugar)
Secreted in response to: Low blood glucose
Secretion inhibited by: High blood glucose
Disease due to deficient action: Some times
nothing, sometimes hypoglycemia
Disease due to excess action: Hyperglycemia
Pancreatic Endocrine Hormones
and Their Purpose
C – Somatostatin ( secreted from hypothalamus )
Purpose: Regulate the production and excretion of
other endocrine tumors
Action: Slows down production of insulin, glucagon,
gastrin, and other endocrine tumors
Secreted in response to: High levels of other
endocrine hormones
Secretion inhibited by: Low levels of other
endocrine hormones
Disease due to deficient action: Poorly defined
Disease due to excess action: Diabetes (inhibits
insulin production), gallstones, and dietary fat
intolerance.
Pancreatic Endocrine Hormones
and Their Purpose
D - Gastrin
Purpose: Assist in digestion within the stomach
Action: Induce acid producing cells of the stomach to
produce acid
Secreted in response to:
Food in the stomach and
intestines
Secretion inhibited by:
Absence of food in stomach
and intestines
Disease due to deficient action:
Poorly defined,
some times no symptoms at all
Disease due to excess action:
Stomach ulcers due
to excess stomach acid
Pancreatic Endocrine Hormones
and Their Purpose
E - Vasoactive Intestinal Peptide (VIP)
Purpose: Help control water secretion
and absorption from the intestines
Action: Causes intestinal sells to secrete
water and salts into the intestines (inhibit
absorption)
Disease due to excess action:
Severe
watery diarrhea and salt (potassium)
imbalances
Delta cell Alpha cell
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‫ينشط افرازها‬
‫من‬
‫ستوماتوستاتين‬
---------
Inhibits
secret
glucagon
Beta
cell
types of
cells
------
Insulin
-------- ‫ينشط افرازها‬
‫من االنسولين‬
Glucagon
‫يثبط افراز‬
‫الجلوكاجون‬
‫ يثبط افراز‬Stomatosta
‫االنسولين‬
tin
Diabetes Mellitus

Diabetes mellitus is an endocrine disorder
characterized by many signs and
symptoms.
Diabetes mellitus is a disorder quite distinct
from the similarly-named diabetes
insipidus. They both result in the
production of large amounts of urine
(diabetes), but in one the urine is sweet
while in the other (caused by ADH
deficiency) it is not. Before the days of
laboratory tests, a simple taste test
("mellitus" or "insipidus") enabled the
doctor to make the correct diagnosis
There are three categories of diabetes
mellitus:
1 - Insulin-Dependent Diabetes Mellitus (IDDM)
[also called "Type 1" diabetes] and
2 - Non Insulin-Dependent Diabetes Mellitus
(NIDDM)["Type 2"]
3 - Inherited Forms of Diabetes Mellitus
Insulin-Dependent Diabetes Mellitus
(IDDM)
 IDDM (also called Type 1 diabetes)
 is characterized by little (hypo) or no
circulating insulin;
 most commonly appears in childhood.
 It results from destruction of the beta cells of
the islets.
IDDM is controlled by carefully-regulated injections
of insulin. (Insulin cannot be taken by mouth
because, being a protein, it would be digested.
However, the U.S. FDA has approved [in January
2006] an insulin inhaler that delivers insulin through
the lungs and may reduce the number of daily
injected doses needed.)
For many years, insulin extracted from the glands of
cows and pigs was used. However, pig insulin differs
from human insulin by one amino acid; beef insulin
by three. Although both work in humans to lower
blood sugar, they are seen by the immune system
as "foreign" and induce an antibody response in the
patient that blunts their effect and requires higher
doses
Two approaches have been taken to solve this problem:
Convert pig insulin into human insulin by removing the one
amino acid that distinguishes them and replacing it with
the human version. This approach is expensive, so now the
favored approach is to
Insert the human gene for insulin into E. coli and grow
recombinant human insulin in culture tanks. Insulin is
not a glycoprotein so E. coli is able to manufacture a fullyfunctional molecule (trade name = Humulin). Yeast is also
used (trade name = Novolin).
Recombinant DNA technology has also made it possible to
manufacture slightly-modified forms of human insulin that
work faster or slower than regular human insulin.
Non Insulin-Dependent Diabetes
Mellitus (NIDDM)
 Many people develop diabetes mellitus without an
accompanying drop in insulin levels (at least at
first).
 In many cases, the problem appears to be a failure
to express a sufficient number of glucose
transporters in the plasma membrane of their
skeletal muscles.
Skeletal muscle is the major "sink" for
removing excess glucose from the blood
(and converting it into glycogen). In NIDDM,
the patient's ability to remove glucose from
the blood and convert it into glycogen may
be only 20% of normal. This is called
insulin resistance.
NIDDM (also called Type 2 diabetes
mellitus) usually strikes in adults and,
particularly often, in overweight people.
However, over the last few years in the U.
S., the incidence of NIDDM in children has
grown to the point where they now account
for 20% of all newly-diagnosed cases (and,
like their adult counterparts, are usually
overweight).
Inherited Forms of
Diabetes Mellitus
• Some cases of diabetes result from mutant genes
inherited from one or both parents. Examples:
• mutations in one or both copies of the gene
encoding the insulin receptor. These patients
usually have extra-high levels of circulating insulin
but defective receptors. The mutant receptors
• a mutant version of the gene encoding
glucokinase, the enzyme that phosphorylates
glucose in the first step of glycolysis
Pancreatitis

An estimated 50,000 to 80,000 cases of
acute pancreatitis occur in the United
States each year. This disease occurs
when the pancreas suddenly becomes
inflamed and then gets better. Some
patients have more than one attack but
recover fully after each one. Most cases of
acute pancreatitis are caused either by
alcohol abuse or by gallstones. Other
causes may be use of prescribed drugs,
trauma or surgery to the abdomen, or
abnormalities of the pancreas or intestine.
What Are the Symptoms of AP?

Acute pancreatitis usually begins with
pain in the upper abdomen that may last
for a few days. The pain is often severe.
It may be constant pain, just in the
abdomen, or it may reach to the back and
other areas. The pain may be sudden and
intense, or it may begin as a mild pain
that is aggravated by eating and slowly
grows worse. The abdomen may be
swollen and very tender. Other symptoms
may include nausea, vomiting, fever, and
an increased pulse rate. The person often
feels and looks very sick.
Chronic Pancreatitis

The term "chronic pancreatitis" defines the
histologic, functional, and clinical results of longstanding or irreversible pancreatic injury. There
are a number of things that increase a persons
risk of deveolping chronic pancreatits including
alcohol consumption, smoking, genetic factors
and other conditions or tramatic events that
injure the pancreas. Within the National Institute
of Health, the National Institute of Diabetes,
Digestive and Kidney Diseases has been give the
challange of addressing the problem of
pancreatitis.
The human pancreas is an
amazing organ with two main
functions: [1] to produce pancreatic
endocrine hormones (e.g., insulin &
glucagon) which help regulate many
aspects of our metabolism and [2],
to produce pancreatic digestive
enzymes.