Compare and Contrast the Endocrine System and the Nervous System
Endocrine =chemical, hormones, long or short distances, fast or slow response time, internal target
Nervous = Chemical/electrical, neurotransmitters, short distances, fast response time, internal and external targets
Both work together to maintain homostasis
What are autocrine signals and paracrine signals
autocrine= takes place within the same cell
Paracrine= induce response in neighboring cell
Describe hormones
The only cells with receptors specific to a given hormone will respond to that hormone.
*help regulate growth, reproduction, metabolism, sleep, fluid balance
If it doesn't fit the receptor, NO RESPONSE
Which hormones are charged? Anions?
Those from Amino Acids= peptides, proteins, amines
*they need a receptor to get through the cell membrane
Which hormones are lipid soluable?
Steroids ( no charge) they stick together, don't like water
Estrogen, testosterone, aldosterone, cortisol
* melt right into the cell membrane, don't need a receptor, theirs are on the inside
Describe the G protein signaling pathway of action for hormones
1.-Ligand( hormone) binds to receptor ( second messenger)
2.-relay info into the cell ( made of G proteins) responsible for relaying hormonal information to downstream pathways
3.-The ligand ( hormone) binds to receptor, hits the enzyme, elicits response
What is downregulation?
excess hormones make the body decrease the # of receptors to lower the response
*they endocytosis, taken into the cell and used somewhere else
ex. Diet high in sugar, overload, insulin binds to receptor, opens door to lower the BS ( wear out receptor) causes t2 diabetes
What is upregulation?
Hormones are in small quantity-produce more receptors so even a small amt of hormones will give a response
Three ways hormones act on target cells
Permissive=enable one to act on another
ex. some reproductive hormones act on thyroid hormone
Synergist= work together to give amplified response
ex. FSH and estrogen=egg maturation
Antagonist= opposing
ex. Insulin ( lowers blood sugar) /Glucagon ( increase Blood sugar)
Describe regulation of hormone release?
Negative and positive feedback loops
Negative= stimulus, response, back to normal
Positive= snowball effect. Stimulus enhanced by response
Give an example of negative feedback loop
Blood sugar increases
insulin released
lowers blood sugar
Give an example of positive feedback loop
ex. hypertension
pressure in arteries
pressure on kidneys
kidney start to fail
more pressure
increased fluid =kidney failure
How do endocrine glands know what they are suppose to do? 3 ways
Humoral
Neural
Hormonal
What is a humoral change
changes in blood levels of non-hormone chemicals
ex. Increase sodium levels, pee more, drink more, response is because of a change
What is a neural change?
hormones are released in response to a neural stimuli
ex. adrenal gland = fight or flight
What is a hormonal change?
endocrine glands secrete hormones in response to another hormone
ex. pituitary gland
What is the master gland and what controls the master gland?
Pituitary gland is master gland controlled by the Hypothalamus
What is the function of the hypothalamus
feeding, fleeing, fighting, reproduction
Name the hormones that come from the anterior pituitary
GH- growth hormone
PRL- prolactin, milk production
TSH- thyroid stimulating
ACTH= from adrenal cortex, corticosteroid hormones
LH-Leutenizing ( like hairy apes) in males, females stimulates follicle maturity and triggers ovulation
FSH- sperm in males,
What is stored in the posterior pituitary
ADH=antidiuretic hormone ( retain fluid), detects osmolality ( level of salt and solute)
Oxytocin= tend and befriend, milk letdown, uterine contractions
Give an example of ADH in action
Eat salty Chinese food
Blood osmolality increases because of sodium
Body tries to retain fluid to dilute the sodium
Acts on kidney tubules to retain the excess water making you thirsty
If you drink alcohol why do you get dehydrated?
Increase in sugar
Increase in urine output
Alcohol inhibits antidiuretic so you loose fluids and feel awful
What is a vasopressin?
it regulates BP by negative feedback
Increase in blood osmolarity
response is to release ADH ( ADH is a vasopressin)
Causes=retention of fluid to balance it
what is a tropic hormone?
Targets other hormones
FSH=gonads
ACTH=adrenal glands
LH=gonads
TSH=thyroid
Where are melanocytes coming from?
intermediate pituitary gland
Discuss GH
Growth hormone is a somatotropin
Anabolic=regulates growth and promotes protein synthesis and tissue building
What are some growth hormone disorders?
Gigantism= excessive GH in children
Acromegaly= in adults, large hands, feet, face
Pituitary dwarfism= low GH
What is the TSH
thyroid stimulating hormone called thyrotropin( t3,t4)
negative feedback ( low t3t4,TSH released or inhibited)
regulates metabolism and calcium homeostasis
Discuss the thyroid gland
thyroid hormone made in colloid cells
needs iodine to facilitate TSH ( it binds to the AA to produce t3, t4)
metabolism, protein synthesis and reproductive hormones, can cause sensitivity to E, NE
What disorder is the cause of a Goiter?
thyroid disorder
not enough iodine, hormone accumulates in the colloid cells
What is hypothyroidism
low thyroid hormone levels
weight gain, cold hands, not producing the energy needed
What is hyperthyroidism?
elevated thyroid hormone
can be from tumor?
increased metabolism, anxiety, trembling
*graves disease
What is the role of calcitonin in they thyroid hormone?
decreases osteoclast activity
ex. too much blood calcium, calcitonin helps inhibit osteoclast to keep more calcium from going into the blood
How is thyroxine released?
TSH bind to receptors (needs iodine to do so) transporting to follicular cells
Iodine binds to the AA in thryroglobulin to produce t3,t4
TSH stimulates the release of t3,t4 into the bloodstream
give and example of negative feedback for thyroid hormone
Low T3T4 stimulate thyrotropin- cause release of TSH which release TsT4 into the bloodstream
High levels of T3T4 decrease the production and secretion of TSH
*thyroid regulates metabolism
How does TH affect mitochondria?
ATP- regulates metabolism
Protein synthesis for tissue and neurological development
Catecholamine- NE,E sensitivity
T4, T3 is what type of system
Second messenger -G protein
What is the key role of the PTH
Parathyroid hormone regulates calcium uptake
It increases blood calcium by stimulating osteoclasts
*causes reabsorption increase of calcium in the kidney tubules
*activates vitamin D which helps in digestion and calcium absorption
What is hyperparathyroidism
Over production of PTH
Bones break, calcium deposits
Hyperparathyroidism?
Low PTH
Low blood calcium
muscle twitches, cramping, spasms, can't build teeth enamel
Describe the adrenal glands
Cortex- endocrine
Medulla- Neural ( E, NE)
*secrete adrenaline-
Lipids
-respond to stress, BP, fluid and electrolyte balance, inflammation
Which layer is aldosterone secreted
Zona glomerulosa ( salt)
Aldosterone increase BP in response to the adrenal hormone.
It causes kidneys retain sodium ( angiotensin- asso. with kidneys and lungs)
What hormone is a synergist to Aldosterone
Aldosterone and ADH- they both retain fluid
What layer are the glucocorticoids in?
Zona Fasiculata- Sugar
Cortisol- increases blood sugar( glucose), inhibits tissue building
inhibits tissue building- down regulates immunity ( inhibits inflammation) so you can do things longer under stress
Which layer is the Androgens found
Zona reticularis- Sex
estrogen and testosterone, sex drive in women
What does the Adrenal Medulla do?
Nervous tissue
Produce NE, E
Catecholamines ( chemical class)
Sympathetic stress pathway
Which hormone increases sodium
Which hormone increased glucose
Aldosterone
Cortisol
What disorder is caused by hypersecretion of cortisol or ACTH
Cushing Disease-fatty deposits in neck and face, rounded face
What is Addison disease
Hypo secretion=low glucose and sodium
* crave salt, weakness, nausea and vomiting, abdominal pain, weightloss
Discuss the function and release of melatonin
comes from pineal gland
influences circadian rhythms
Compare and contrast the two major pancreatic hormones
Insulin= lowers blood glucose ( facilitates glucose uptake)
Glucagon= increases blood glucose. Stimulates the liver to convert glycogen back to glucose ( glycogenolysis)* breaks down excess sugar
Where are the hormones of the pancreas secreted from
islet of langerhans
What do the alpha cells secrete
Glucagon- increase blood glucose to break down excess sugar ( glucose) 15-20 mins
Give an example of Glycogenolysis
When you don't eat , breakdown glycogen stored in liver
What hormone is secreted from the beta cells?
Insulin. ( gets produced in response to high glucose levels)
Lowers blood sugar
* opens the door to push glucose into the cell quickly to lower the blood sugar
What causes type 2 diabetes
Excess sugar consumption wears out the receptors because insulin is always high
What turns glucose into glycogen
Glucagon stimulates glucose to breakdown into glycogen
What hormone is from the heart
ANP- atrial natriuretic peptide- it reduces sodium, water
vasodilator- opens the blood vessels
What is an Antagonist of ANP
Aldosterone- increases BP while ANP decreases BP
ANP= amy needs to pee
Describe Aldosterone again
It is a mineralocorticoid- raises BP
Secreted by the adrenal cortex in response to a drop in BP.
Tells the kidneys to retain sodium