Transcript Endocrine System

Endocrine System
Endocrine System—General Info
• Works WITH the Nervous system
• Main function is to produce hormones—
chemical messenger influencing other
tissues/organs.
• Differs from NS with regard to speed
– NS—body will make rapid adjustments to
changes
– ES—uses chemical messengers (hormones) to
affect change. Hormones travel via
bloodstream. Generally longer lasting.
Endocrine vs Exocrine glands
• Endocrine glands—secrete hormones directly
into the blood
– anterior pituitary
– thyroid
– adrenal
• Exocrine glands—deliver hormones into the
blood via tubes leading from the gland
– sweat glands
– salivary glands
– mammary glands
Major body processes regulated by
ES
• Reproduction
• Growth and development
• Maintaining homeostasis of electrolytes,
water and nutrients
• Regulation of cellular metabolism
Target cells and controlling the ES
• Hormones travels through the entire body
via the blood, but only affect specific target
tissues.
• The body primarily uses negative feedback
loops to determine when to turn on/shut off
hormone production.
• Other ways the body controls the ES is
through the nervous system and biorhythms.
ENDOCRINE REGULATION
A fuzzy balancing act
Receive, Reaction, Refine
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Endocrine Regulation
RECEIVE
Sensory/Humoral input
• response to substance in the blood
(Iodine, glucose)
Hormonal regulation
• responds to upstream gland
regulation (TSH, LH...)
Neural regulation
• response short term stress
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Endocrine Regulation
REACT
• Hormones travel through the blood and bind
to receptor proteins
– Steroid hormones (cholesterol derived)
• Are lipid soluble and cross the plasma membrane,
bind to receptors inside the cell and affect DNA
transcription.
– Animation
– Non-steroid hormones (protein based)
• Bind to specific membrane receptors and trigger a
signaling cascade inside the target cell which
activates necessary enzymes.
– Animation…
Endocrine Regulation
REACT
Steroids
• Lipid soluble - readily enter cells
– stimulus leads to biosynthesis
– transport in blood assisted by carrier proteins
(serum albumin)
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Endocrine Regulation
REACT
Non steroids
• Water Soluble – can travel through blood freely, but
have to interact with membrane receptors (can’t
cross lipid bilayer). Once docked, will set cause
changes within cell.
– Protein is synthesized, packaged into vesicles via
golgi bodies
– vesicles migrate to and collect at release site
– exocytosis to dump contents into bloodstream
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REFINE:
Negative Feedback loops
• Works like a thermostat in your house
to maintain a constant environment of
68oF.
– Turns on the furnace to produce
heat if the temperature is too cold
and off when the desired temp is
reached.
– Turns on AC to cool the house if
temp is too high and shuts it off
when back to the desired temp.
http://www.endocrinesurgeon.co.uk/endocrine_conditions/What-is-negative-feedback.html
REFINE:
Homeostasis
• ensure the body
returns to
“normal”
conditions after
stimulus.
www.mdmaterials.com
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http://www.thetruthisbliss.com/wp-content/uploads/2009/11/Calcium-Regulation.jpg
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Glucose Regulation
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Biology, Campbell. 1987. pg 896
Negative Feedback Loop--egs
• Hypothalamus
receives input and
reacts to stimulate
specific organs to
achieve the desired
effect.
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Negative Feedback
Loop--egs
• Feedback system
for the control of
ovulation
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Biology:An Exploration of Life, McFadden&Keeton. 1995. pg 546
Positive Feedback Loop
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Endocrine Regulation
Endocrine
System
REFINE
Removal of hormones
•The bulk of hormone is cleared by the liver and kidneys
•Only a small fraction is removed by target tissue
– Steroid (and thyroid hormones) are degraded after hormonereceptor complex binds to DNA
• action and elimination are slower (hours-days)
– protein and amine hormones (non steroids) bind to receptors
and are internalized and degraded
• action and elimination is usually quicker (minutes)
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Endocrine Pathologies
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Endocrine Disorders
Endocrine
Problems
Dwarfism
Characteristics
-Short stature
(proportional)
Cause
shortage of GH (hypophysial dwarfism)
or defective receptor (Laron Syndrome).
www.blogsmonroe.com
Endocrine Disorders
Gigantism
CharacteristicsExtreme height
(8-9 ft, proportional structures)
CauseExcessive GH during
development
Gigantism is extremely rare (only a few hundred known cases total).
Cause of excess of GH excess varies but often is linked to23Acromegaly
www.endotext.org
Endocrine Disorders
Endocrine
Problems
AcromegalyAcromegalyCharacteristics
Causeexcess
GH
in adulthood.joint aches
abnormal
bone
growth
thick coarse
oily skin
Usually
benign
adenoma impaired vision
excessive sweating
sleep apnea
abnormal menstruation
skin odor
erectile dysfunction
headaches
fatigue and weakness
decreased libido
enlarged lips nose and tongue
skin tags
www.addamsfamily.com
Endocrine Disorders
Hypothyroidisim
CharacteristicsCause
- Not enough thyroid hormone.
Fatigue, weakness, weight gain or
resistance to weight loss, course dry hair,
Hasimoto’s
dry roughdiseasepale skin, autoimmune
hair loss, cold disease
intolerance, muscle cramps and aches,
constipation, depression, irritability,
Medical
treatmentshormone
replacement
memory
loss, abnormal
menstruation,
decreased libido.
thyroid.about.com
High TSH with low T3/T4.
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www.datiskharrazian.com
Endocrine Disorders
– Hyperthyroidism
CausesCharacteristicspalpitations,
heat disease
Graves’ Disease:
autoimmune
intolerance,
nervousness,
(antibodies
attach toinsomnia,
thyroid and over
breathlessness,
increased
BM, decreased
stimulate T3
production)
menstruation, fatigue, fast heart rate,
trembling,
muscle
weakness,
Benignweight
tumor-loss,
nodule
(few
cells)
warm moist skin, hair loss, staring gaze.
out of regulation
pro.corbis.com
LowThyroiditisTSH
temporary swelling
high T3/T4
levels (postpartum)
– of gland
www.avondalevet.com
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Endocrine Disorders—Hyperthyroidism
con’t:
• Treatment-antithyroid medication,
radioactive iodine and possibly
surgery (if trouble swallowing or
initial treatments don’t work.
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Endocrine Disorders
Cushing’s Disease
Characteristicscentral body obesity
glucose intolerance
Hypertension
menstrual irregularity
“Buffalo hump”
Osteoporosis
kidney stones
excess hair growth
emotional liability
“moon” face
Cause- Excess Cortisol
tumor of the lungs, pituitary or
adrenal glands
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ourlatinamerica.blogspot.com
Endocrine Disorders
DiabetesMost common Endocrine disorder
Consistent elevated blood sugar
Characteristics- frequent hunger, thirst, urination,
blurred vision, fatigue, weight loss, poor wound
healing, dry mouth, dry itchy skin, impotence,
recurrent infections. Erratic blood sugar.
– normal blood glucose: 80-120mg/100 ml,
– diabetes: as much as 600mg/100ml of blood
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www.malluworld.org
Endocrine Disorders
Diabetes
CausesType 1 -insulin deficiency
Type 2 -insulin resistance
hormone disturbance
Agromegaly
Cushing’s
Gestational diabetes- temporary condition caused
by pregnancy
placenta metabolizes insulin quickly.
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Endocrine Disorders
ENDOCRINE
DISORDERS
Adrenal disorders:
Adrenal insufficiency
Addison's disease
Congenital adrenal hyperplasia
Mineralocorticoid deficiency
Conn's syndrome
Cushing's syndrome
adrenogenital syndrome
Pheochromocytoma
Adrenocortical carcinoma
GRA/Glucocorticoid remediable
aldosteronism
Glucose homeostasis disorders:
Diabetes mellitus
Hypoglycemia
Idiopathic hypoglycemia
Insulinoma
Metabolic bone disease:
Osteoporosis
Osteitis deformans (Paget's
disease of bone)
Rickets and osteomalacia
Pituitary gland disorders:
Diabetes insipidus
Hypopituitarism
Pituitary tumors
Pituitary adenomas
Prolactinoma
Acromegaly, gigantism
Cushing's disease
Parathyroid gland disorders:
Primary hyperparathyroidism
Secondary hyperparathyroidism
Tertiary hyperparathyroidism
Hypoparathyroidism
Pseudohypoparathyroidism
Sex hormone disorders:
Disorders of sex development or
intersex disorders
Hermaphroditism
Gonadal dysgenesis
Androgen insensitivity syndromes
Hypogonadism
Gonadotropin deficiency
Kallmann syndrome
Klinefelter syndrome
Ovarian failure
Testicular failure
Turner syndrome
Disorders of Gender
Gender identity disorder
Disorders of Puberty
Delayed puberty
recocious puberty
Menstrual function or fertility
disorders
Amenorrhea
Polycystic ovary syndrome
Thyroid disorders:
Goiter
Hyperthyroidism and GravesBasedow disease
Hypothyroidism
Thyroiditis
Thyroid cancer
Tumours of the endocrine glands
not mentioned elsewhere
Multiple endocrine neoplasia
MEN type 1
MEN type 2a and
31 2b
Review of Endocrine
System
• Quick review of
info…
• Amazing Podcast!
Endocrine System
• Glands and the hormones they
produce…you will need to know these for
the test.
• Study earlier rather than later!
Hypothalamus
a region of the brain, between the
thalamus and the midbrain, that functions
as the main control center for the
autonomic nervous system by regulating
sleep cycles, body temperature, appetite,
etc., and that acts as an endocrine gland
by producing hormones, including the
releasing factors that control the
hormonal secretions of the pituitary
gland.
Hypothalamus Gland
Hormones
• TRF
–Responsible
for
stimulating
Pituitary to
release TSH
en.wikipedia.org
Hypothalamus Gland
Hormones
• Oxytocin
–Responsible
for causing
uterine
contractions
during and
after birth.
Hypothalamus Gland
Hormones
• GHRH (growth
hormone releasing
hormone)
–Responsible for
triggering release of
GH from pituitary
www.uscnk.com
Hypothalamus Gland
Hormones
• GnRH (gondatropin
releasing hormone)
–Triggers release of
FSH from pituitary.
commons.wikimedia.org
Pituitary
• Known as the master gland
as it is not only responsible
for many hormones, it also
acts as a regulator for other
glands in the endocrine
system.
Pituitary Gland Hormones
• ADH
(Antidiuretic
Hormone)
–Responsible for
maintaining
water balance
in your body.
Pituitary Gland Hormones
• GH (Growth Hormone)
–Causes growth in humans…big
surprise huh?
Pituitary Gland Hormones
• TSH
(Thyroid
Stimulating
Hormone)
–Influences
your
thyroid
gland
Pituitary Gland Hormones
• ACTH
(Adrenocorticotropic
Hormone)
–Regulates the
adrenal glands
Pineal Gland
Pineal Gland Hormone
• Melatonin
–Helps your
body adjust to
various
amounts of
daylight
Thyroid Gland
Location: Surrounds windpipe
Thyroid Hormones
• Thyroxine
–If iodine is
present, it will
control the
metabolism of
glucose in the
body.
Thyroid Hormones
• Calcitonin
–Responsible
for depositing
blood calcium
into bones
Parathyroid Glands
• Location—
attached behind
the thyroid
– Years ago, they used to
remove the
parathyroids with the
thyroid if the thyroid
was damaged. This
lead to death in
patients…OOPS!
Parathyroid Hormone
• PTH (Parathyroid
hormone)
– Responsible for
pulling calcium
from bones and
depositing it into
the bloodstream.
Thymus Gland
• Location:
Longish gland in
the middle of
your chest.
Thymus Hormone
• Thymosin
–Assists the immune
system
Adrenal Glands
Location: Located
right on top of kidneys
Adrenal hormones
• Aldosterone
–Maintain
blood salts
(primarily
Na+, K+)
Adrenal hormones
• Cortisol:
– Kicks in to help
body with long
term stress.
Adrenal hormones
• Epinephrine
– Kicks in when
body undergoes
short term stress
– Test-taking, car
accident, caught
in a lie…etc.
Pancreas
• Location:
Found right
behind the
stomach
Pancreas hormones
• Insulin
–Decreases
blood sugar
Pancreas hormones
• Glucagon
–Increases
blood sugar
Ovaries
• Small, almond shaped organs on
the ends of the fallopian tubes.
Ovary hormones
• Estrogen and
Progesterone
– Responsible for
sex characteristics
and controlling
the menstrual
cycle
Testes
• Testosterone
– Responsible for male secondary sex
characteristics
Other structures and the ES
• Placenta
–Estrogen and Progesterone help
maintain uterus health
–Lactogenic Growth hormone
help with milk production after
birth of baby