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Regulation of hormone secretion
Introduction
Humoral regulation
Hormonal regulation
Neural regulation
Endocrine diseases
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Cont.
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Introduction
• Hormones
• Endocrine system essentials
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Introduction
• The living body possesses a remarkable
communication system to coordinate its biological
functions
• nervous system- coordinates the body functions
through the transmission of electrochemical
impulses
• The endocrine system acts through a wide range
of chemical messengers known as hormones
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Hormones?
• chemical signals that coordinate a range of bodily
functions.
• as the chemical messengers involved in the
transmissions of information from one tissue to
another and from cell to cell
• hormone disorder-hormone levels are too high or
too low
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Endocrine system
• is made up of a network of glands
• to regulate many bodily functions
(growth and metabolism)
• Endocrine diseases occur when
glands produce an incorrect amount
of hormones
• Endocrine system helps control :
• Growth and development
• Metabolism (digestion, breathing,
maintaining body temperature)
• Reproduction
• Mood
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Hormone
secretion
Can be activated
Humoral
regulation
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Hormonal
regulation
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Neural
regulation
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Humoral regulation
• Humoral – refers to the fluid of the
body, in other words, the extracellular
fluid (ECF, which includes the blood
plasma)
• ECF – body fluid that is not contained
in cells
• The endocrine cell responds to
changes in the concentration of a
substance in the ECF
• The hormones act to stabilize and
maintain the concentration of the
substance within the appropriate
physiological range.
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Cont.
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Cont.
Examples
Parathyroid hormone (PTH)
• Is the most important endocrine
regulator of calcium and phosphorus
concentration in extracellular fluid
• Is secreted from cells of the parathyroid
glands and finds its major target cells in
bone and kidney.
• Secreted by parathyroid gland and
plays role in calcium homeostasis
• PTH is secreted during hypocalcemia,
hence, PTH functions increase the
amount of ECF calcium concentration
in the body
• Hypocalcemia is the presence of low
serum
calcium levels in the@MAHSA
blood
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Hormonal regulation
• Hormone binding to its receptor on an
endocrine cell to regulate hormonal
secretion
• Tropic hormone
• A hormone that stimulates hormone
secretion
• Also stimulate proliferation of endocrine
cells
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Neural regulation
• Occur when neuronal input to an
endocrine cell increases or
decreases hormonal secretion
• Examples: Adrenal Medulla
• The adrenal gland is a composite
endocrine gland: the outer layer is
called the adrenal cortex and the
inner layer is called the adrenal
medulla.
• Epinephrine and norepinephrine are
considered hormones because they
are released to the circulation.
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Endocrine disease
• hormone disorder-hormone levels are too high or
too low
• Influence hormone levels:
• Stress
• Infection
• changes in the blood's fluid and electrolyte
balance
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Endocrine
diseases
Endocrine gland
hyposecretion
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Endocrine gland
hypersecretion
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Tumours of
endocrine
glands
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Endocrine gland hyposecretion
• too few hormones are released from a gland
• Example of hyposecretion in growth
hormone is pituitary dwarfism
• Symptoms of dwarfism:
• Short fingers
• Limited mobility at the elbows
• A disproportionately large head, with a
prominent forehead and a flattened
bridge of the nose
• An adult height around 4 feet (122 cm)
• Treatment for dwarfism:
• Hormone therapy started during the
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growth
process
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Endocrine gland
hypersecretion
• When too many hormones are secreted from a
gland
• Example of hypersecretion in growth hormone is
gigantism in children and acromegaly in adults
• Symptoms of gigantism:
• very large hands and feet
• a prominent jaw and forehead
• flat noses and large heads, lips, or tongues.
• thick toes and fingers
• Treatment for gigantism:
• Surgery removing the tumor (optional)
• Drugs pill to lower growth hormone levels
(bromocriptine and cabergoline)
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Tumours of endocrine
glands
• Endocrine tumor arises from cells that produce hormones,
the tumor itself can produce hormones and cause serious
illness
• Example - thyroid cancer. Begins in the thyroid gland,
which is located in the front of the neck just below voice
box
• Symptoms of thyroid cancer:
• Neck swelling
• Cough that is not due to a cold or other issue
• Difficulty swallowing and breathing
• voice changes
• Treatment:
• surgery,
• Radiation
• 5/9/2016
hormone treatments
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