Download The Endocrine System

The Endocrine System
Hormones
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For hundreds of years, humans have released countless numbers of
synthetic compounds into the environment. Many pharmaceuticals,
cleaning products, cancer treatments and pesticides are known endocrine
disruptors and have disastrous effects on fish populations.
Largemouth Bass commonly affected by endocrine disruptors
Endocrine disruptors that mimic estrogen hormones have a severe impact
on fish fertility and reproduction. They can lead male fish to undergo
feminization, a process where males turn into females. They experience a
serious decrease in testosterone level and many male fish are found with
immature female eggs in their testes. Exposure to estrogen does not stop
with the intersex problem. It also reduces production of immune-related
proteins in fish which makes them more susceptible to disease.
“Our research suggests that estrogen-mimicking compounds may make fish
more susceptible to disease by blocking production of hepcidin and other
immune-related proteins that help protect fish against disease-causing
bacteria,” said Robertson.
What are hormones?
• Hormone – chemical signal made in one
place and travels through body to a target
organ
• Enable body to maintain homeostasis
Where are hormones produced?
• Various “glands”
– Pineal gland, hypothalamus, pituitary gland,
thyroid gland, parathyroid gland, thymus
gland, adrenal glands, pancreatic islet cells,
ovaries, uterus, and testes
Endocrine Overview
Gland
Hormone Made
Target
Effect(s)
Hypothalamus
Various
Various
Main controller of the
endocrine system
Pituitary Gland (directly
controlled by
hypothalamus)
Various Growth
hormone, Fsh, LH,
Adrenal gland and
thyroid gland
Various
Adrenal glands
Epinephrine,
norepinephrine, cortisol
Various
Fight-or-flight response
Various cells in body
Prostaglandins
Various
Fever, cramps,
inflammation
Pancreas
Insulin, glucagon
Cells in body, liver
Regulates bloodglucose levels
Pineal
Melatonin
Gonads
Inhibits reproductive
activites, sleep
Endocrine Overview Cont.
Gland
Hormone Made
Target
Effect(s)
Parathyroid
Parathyroid hormone
Bone, kidney
Elevates calcium levels
in blood
Thymus
Thymosin
Lymphocytes
Plays role in immune
response
Ovary
Estrogens,
Progesterone
Female reproductive
structures
Maturation of
reproductive organs,
prepares uterine lining
for pregnancy
Testis
Testosterone
Male reproductive
structures
Maturation of
reproductive organs
Thyroid
, Thyroxine, calcitonin
Various
Growth, speeds up
metabolism, decreased
calcium levels in blood
How Hormones Work
• Bind to receptors on cell surface (peptide
hormones) or in cell nucleus (steroid hormones)
• Hormones alter what genes/enzymes are turned
on and off in the target cell
• Steroid hormones can travel through cell
membrane and nuclear membrane
• Peptide hormones cannot travel through cell
membrane
– Use second messengers to transfer signal
The ‘Master Gland” and its Master
Endocrine Disorders
• Goiters – too little thyroxine in blood
stream
• Diabetes – too little insulin produced or
insulin receptors not functioning properly
on cells
Goiter
Endocrine Disorders Cont.
• Dwarfism – growth
hormone from pituitary
gland inhibited
• Gigantism – growth
hormone from pituitary
gland hyperactive
• Too much growth
hormone during
adulthood
Acromegaly
To much growth hormone
Tallest meets shortest man
• 1 foot 9.5 inches meets 8 feet 11.1 inches
Killed wife w/ cord, son strangle
hold (7yrs old) & self -hung(40 yrs
old)
• Was given to much
testosterone for his
hormone disorder 10
time the normal levels
hyperthyroidism
Cretinism to little thyroxin
Some affect fat deposits in the
lower extremities
Hormone disorder Diabetes
mellitus (I)
• Not enough Insulin
• Type I
Addison's Disease
• Addison's disease is a
chronic condition that
results when the adrenal
glands are unable to
produce enough of
certain important
hormones. This can lead
to fatigue, low blood
pressure, loss of appetite,
and darkening of the skin.
Cortisol and
aldosterone deficient
•
Increased levels of Parathyroid
hormone -calcium
Estrogen decificency
Testosterone differences
Gynecomastia / estrogen
Oxcitocin
Cushing's syndrome
• occurs when your
body is exposed to
high levels of the
hormone cortisol
for a long time
Cat endocrine disorders