The Adrenal Gland & Stress
Regulation
Adrenal
Gland
What Is the Adrenal Gland?
-The adrenal glands are two triangular glands,
one placed on top of each kidney.
- They are the glands that produce hormones
that primarily relate to stress
The Adrenal Gland Overview
The adrenal cortex is responsible for the outermost part of
Gland and is responsible for the production of
Mineralocorticoids and Glucocorticoids
The Adrenal Medulla is the inner part of the gland and is
Responsible for the production of epinephrine and
Norepinephrine
Why is it part of the Endocrine System?
-The Endocrine system is -The adrenal gland
a hormone pruduction
produces hormones
system that controls
that affect the way the
many of the slow
body copes and reacts
moving processes
to different situations.
within our body such
Ie. Releasing
as cell growth.
Adrenalin to deal with
stress
The Two Parts of the Adrenal Gland
-The
outer region known as the cortex secretes hormones
which have important effects on the way in which energy
is stored and food is used, on chemicals in the blood, and
on characteristics such as hairiness and body shape.
Hormones Produced-(Cortex)- Hydrocortisone,
corticosterone, aldosterone and androgen
-The smaller, inner region known as the Medulla is part of the
sympathic nervous system and is the body's first line of
defence and response to physical and emotional stresses.
Hormones Produced -(Medulla)- Epinephrine, norepinephrine
Cortex Functions: Key Hormones
and what they do
•
hydrocortisone hormone
This hormone, also known as cortisol, controls the body's use of fats, proteins,
and carbohydrates.
•
corticosterone
This hormone, together with hydrocortisone hormones, suppresses
inflammatory reactions in the body and also affects the immune system.
•
aldosterone hormone
This hormone inhibits the level of sodium excreted into the urine, maintaining
blood volume and blood pressure.
•
androgenic steroids (androgen hormones)
These hormones have minimal effect on the development of male
characteristics.
• Overview: The adrenal cortex regulates use of various functions
that relate the retention of ions, the use of fats, proteins and carbs
and development of certain characteristics
Medulla Functions
•
epinephrine (Also called adrenaline.)
This hormone increases the heart rate and force of heart contractions,
facilitates blood flow to the muscles and brain, causes relaxation of smooth
muscles, helps with conversion of glycogen to glucose in the liver, and other
activities
•
norepinephrine (Also called noradrenaline.)
This hormone has little effect on smooth muscle, metabolic processes, and
cardiac output, but has strong vasoconstrictive effects, thus increasing blood
pressure.
Overall: Increases blood pressure to deal with stressful situations that the
body may encounter
Examples Of Homeostatic Mechanisms
Of The Adrenal Gland
• Epinephrane and Norepinephrane- Raise blood sugar and
fatty acid levels and also increase heart rate during times of
stress
• Glucocorticoids- Natural steroid used as an anti-inflammatory
• Mineralocorticoids- Promote salt reabsorption in the kidneys
back to the blood stream
Roles Of Glucocorticoids
In Homeostasis
  One role of the Glucocorticoids, such as cortisol, is to work in our
bodies as an anti-inflammatory.
  They depress the immune system to dull the effects of inflammation
when a part of the body is irritated by damage or injury to tissue.
  This prevents or reduces the negative effects of inflammation such as
redness, swelling, heat, and pain.
  They also assist in glucose homeostasis by stimulating
gluconeogenisis in the liver, which initiates the conversion of fats and
proteins into glucose when needed.
Overview of the Adrenal
Gland and Homeostasis
• The adrenal gland contributes to homeostasis
in the following ways:
  Provides excess amounts of energy to the
muscles in emergencies to prevent them from
tiring
  Keeps blood pressure from dropping
• Contributes to the maintaining of electrolytes
and water in the blood stream
Roles of Epinephrine and
Norepinephrine in Homeostasis
•
In emergencies, our adrenal gland is signaled to release epinephrine
and norepinephrine (also known as adrenaline).
•
These chemicals override our body’s usual control of glucose, and
homeostasis for glucose is altered.
•
Adrenaline breaks down glycogen into glucose to produce larger
amounts of ATP in times of stress to produce the energy we need.
•
This leads to increased breathing and heart rate to meet the demands
of the ATP production.
•
Once the emergency is over, adrenaline is produced by the adrenal
gland at a much lower rate, and regular glucose homeostasis is
resumed
Stress
- - In stressful situations epinephrine and
norepinephrine are released from the adrenal
medulla into the bloodstream.
-Norepinephrine responsible for the “fight or
flight” response.
-Epinephrine increases heart rate and cell
metabolism – faster energy source.
Adrenal Gland Hormones
-Different hormones produced in both
cortex and medulla.
- Hormones secreted directly into the
bloodstream.
What are the hormones produced
and their effect?
• Adrenal cortex: secretes hormones
that have an effect on the body’s
metabolism, on chemicals in the blood, and
on certain body characteristics.
• Four different hormones produced in
cortex: hydrocortisone, corticosterone,
aldosterone, and androgen hormones.
• Takes instructions from the pituitary gland.
Hormones Produced contd
• - Adrenal medulla: the body's first line of
defense and response to physical and
emotional stresses.
• - Two different hormones produced in
medulla: epinephrine and norepinephrine
regulate “fight or flight” response.
-Takes instructions form the nervous system.
Cushing’s Syndrome
• ~ Cushing’s syndrome occurs when the body’s
tissues are exposed to high levels of cortisol for too
long. Many people develop Cushing’s syndrome
because they take glucocorticoids—steroid hormones
that are chemically similar to naturally produced
cortisol—such as prednisone for asthma, rheumatoid
arthritis, lupus, and other inflammatory diseases.
Glucocorticoids are also used to suppress the
immune system after transplantation to keep the
body from rejecting the new organ or tissue.
• ~develop Cushing’s syndrome because their
bodies produce too much cortisol. Normally,
the production of cortisol follows a precise
chain of events. First, the hypothalamus, a
part of the brain about the size of a small
sugar cube, sends corticotropin-releasing
hormone (CRH) to the pituitary gland. CRH
causes the pituitary to secrete
adrenocorticotropin hormone (ACTH), which
stimulates the adrenal glands. When the
adrenals, which are located just above the
kidneys, receive the ACTH, they respond by
releasing cortisol into the bloodstream
• ~ Symptoms are as following most people
with the disorder have upper body obesity, a
rounded face, increased fat around the neck,
and relatively slender arms and legs. Children
tend to be obese with slowed growth rates.
• Other signs appear in the skin, which
becomes fragile and thin, bruises easily, and
heals poorly. Purple or pink stretch marks
may appear on the abdomen, thighs,
buttocks, arms, and breasts. The bones are
weakened, and routine activities such as
bending, lifting, or rising from a chair may
lead to backaches and rib or spinal column
fractures.
~Other common signs and
symptoms include
•
•
•
•
•
•
•
1.severe fatigue
2.weak muscles
3.high blood pressure
4.high blood glucose
5.increased thirst and urination
6.irritability, anxiety, or depression
7.a fatty hump between the shoulders
Addison’s disease
• ~ Causes failure to produce adequate levels of
cortisol
• ~ Symptoms are
 1
Chronic, worsening fatigue
 2
Muscle weakness
 3
Loss of appetite
 4
Weight loss
• About 50 percent of the time, one will notice
 1
Nausea
 2
Vomiting
• Diarrhea
Other symptoms include
1
Low blood pressure that falls further when
standing, causing dizziness or fainting
 2
Skin changes in Addison's disease, with areas
of hyperpigmentation, or dark tanning, covering
exposed and non-exposed parts of the body; this
darkening of the skin is most visible on scars; skin
folds; pressure points such as the elbows, knees,
knuckles, and toes; lips; and mucous membranes
• ~Leaves a craving for salty foods
• ~ Treatments involve replacing or substituting the
hormones that are not being made by the adrenal
glands
•
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

•
Cortisol performs vital tasks in the body including

helping maintain blood pressure and cardiovascular function

reducing the immune system’s inflammatory response

balancing the effects of insulin, which breaks down glucose for energy
regulating the metabolism of proteins, carbohydrates, and fats