Download Endocrine Glands and Diseases

Pituitary Gland
“The Master Gland”
• 2 Functional Lobes
*Anterior Lobe
*Posterior Lobe
• Interacts closely with the
Nervous System
through the
hypothalamus.
• Protected by what
structure?
Anterior Pituitary
• Regulated through humoral
stimulation from the hypothalamus.
• Many of the hormones released are
Trophic Hormones.
Anterior Pituitary Hormones
• GH – Somatotropin – promotes mitosis
– Too much = Gigantism or Acromegaly
– Too little = Dwarfism
• PRL – Prolactin – promotes breast milk
production during gestation and nursing
– Hyperprolactinemia = can disrupt fertility and
menstruation
– Hypo-secretion = lack of milk production
• ACTH - Adrenocorticotropic Hormone –
promotes the adrenal gland to release its
hormones
– Hypersecretion = Cushing’s Syndrome
– Hyposecretion = loss of cortisol release by adrenal
glands
Anterior Pituitary Hormones
• TSH - Thyroid Stimulating Hormone –
promotes the thyroid gland to release its
hormones
– Hyposecretion can lead to hyperactive thyroid
– Hypersecretion can lead to hypoactive thyroid and
production of a Goiter
• GRN – Gonadotropin Releasing Hormone –
promotes activity in gonads
– Hyper- and hypo- secretion can both lead to
infertility
Too Much Growth Hormone
• Acromegaly is caused by
too much growth hormone
AFTER puberty has
completed.
• Gigantism is caused by too
much growth hormone during
adolescence and puberty.
Too Little Growth Hormone
• The girl below is pictured
with her father at the age of
5 years.
• The man on the left is
25 years old. The man
on the right is 22 years
old.
Abnormal TSH secretion
Goiter formation due to inadequate
iodine consumption.
Posterior Pituitary Hormones
• Oxytocin – stimulates labor contractions
during delivery
– Lack of oxytocin during labor and delivery
requires administration of PITOCIN to
prompt contractions.
• ADH – Antidiuretic Hormone – prevents
loss of water from kidneys to bladder
during times of dehydration.
– Diabetes insipidis – loss of too much water
– Polydipsia – excessive thirst
Thyroid Gland
• Located in the
anterior portion of
the neck, just below
the throat.
• Releases hormones
that act on the
metabolic rate.
*T3: triiodothyronine
*T4: thyroxine
• Calcitonin –
maintains blood
calcium levels
Thyroid Gland
• T3: triiodothyronine & T4: thyroxine
– High levels of these hormones can increase
metabolic rates
– Low levels of these hormones can decrease
metabolic rates
• Calcitonin
– Low levels can result osteoporosis and
kidney stones since blood calcium is not
being placed into the bones
Parathyroid Gland
• Located on the
posterior
surface of the
Thyroid gland.
• Parathyroid
Hormone (PTH)
Parathyroid Gland
Parathyroid Hormone (PTH)
• The MOST important regulator of blood
calcium levels.
• Low levels of PTH result in muscle
spasms and heart palpitations
• High levels of PTH result in
osteoporosis, too much calcium is being
taken from bones
Adrenal Glands
• Located on the
superior aspect
of each kidney
• 2 functional parts
* Cortex
* Medulla
Each part secretes a
specific type of
hormone.
Adrenal Gland Divisions
CORTEX
MEDULLA
• MINERALOCORTICOID • CORTICOSTEROIDS
– controls fluid and
electrolyte balance
– Example - aldosterone
• Produces sex hormones
– Example – androgens and
progesterone
– Controls sympathetic/
parasympathetic
function
– Example – cortisol and
epinephrine
(adrenaline)
Pancreas
• Located in
abdominal cavity
behind stomach.
• Produces hormones
for the use and
storage of glucose
– Insulin – allows
glucose to absorb
into cells
– Glucagon – removes stored glucose from
liver and fat cells
Pancreas
Insulin
– Too little – diabetes mellitis – inability to use
sugar to make ATP
– Too much – hypoglycemia – low blood sugar
Glucagon
– Too much – glucagonoma caused by tumor
of pancreas leads to symptoms much like
diabetes
– Too little – chronic low blood sugar due to
inability to release glucose from liver and fat
cells
Pineal Gland
• Close to the optic nerve in the brain.
• Produces Melatonin - sleep-wake cycles.
Disorders of Pineal Gland
• Decreased melatonin levels are
associated with
– Insomnia
• Chronic Fatigue Syndrome
– Panic Disorders
– Depression
• SAD – Seasonal Affective Disorder
– Peptic ulcers
Thymus
Gland
• Located behind the
sternum.
• Decreases in size as
you age.
• Produces Thymosin
needed for the
production of Tlymphocytes.
T-cells are needed for protection against viral
infections, fungal infections, and cancer development
Thymus
Gland
• Both high and low levels of thymosin cause
immune dysfunction.
– Too little thymosin results in lack of immune response
– Too much thymosin causes havoc for the immune
system and it does not respond correctly
Gonads: Ovaries and Testes
• Hormone producing glands of the female and
male reproductive systems.
• Controls fertility, reproduction, and gestation.
Testes produce testosterone
Ovaries produce estrogen
Other Hormone-Producing
Organs/Tissues
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•
•
•
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Placenta
Stomach
Intestines
Heart
Striated muscles
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Skin
Adipose/Fat
Liver
Kidneys
Uterus