endocrine system ii

what are two ways the hypothalamus controls the pituitary gland

neurohormones travel through the hypophyseal portal system to anterior pituitary and hypothalamic neurons send axons directly into posterior pituitary

for the anterior pituitary mechanism: neurohormones are released from the __ (hypothalamus) and are secreted to primary plexus where they bind to receptors located on the epithelial cells (secondary plexus) on the anterior pituitary and release a second set of hormones

hypothalamic neurons

why are the neurohormones released from the hypothalamic neurons not considered NT

travel via bloodstream

what is hypophyseal portal system

specialized capillary portal system that carries hypothalamic hormones directly to the anterior pituitary because hypothalamus has no direct contact with anterior pituitary

all hormones are amino-acid based (bind to surface receptors) except for 3 that are lipid-based (name them)

cortisol, aldosterone and androgens

what tissue type makes up the anterior pituitary

glandular epithelial tissue

what tissue type makes up the posterior pituitary and hypothalamus

nervous tissue

why is the posterior pituitary not considered a “true” endocrine gland

does not synthesize hormones; stores and releases hormones made by hypothalamus

what are the six neurohormones secreted by anterior pituitary gland

growth hormone releasing hormone, thyroid releasing hormone, adrenocorticotropic hormone, follicle stimulating hormone, luteinizing hormone, and prolactin

which hypothalamic neuron stimulates/triggers GH release

growth hormone releasing hormone

which gland releases GH (growth hormone)

anterior pituitary

what are the GH target cell/organs

liver, bone, cartilage, muscle, fat and other body tissues

what are the major effects/responses of GH

spares glucose, bone, cartilage and muscle growth, lipolysis (for more energy)

what is pituitary dwarfism

too little GH during childhood

what is gigantism

too much GH in childhood (before epiphyseal plates close)

what is acromegaly

too much GH in adults (after growth plates close)

what are the three homeostatic imbalances related to GH

pituitary dwarfism, gigantism and acromegaly

what is the GH pathway

hypothalamus - GHRH - anterior pituitary - GH - liver/bone/muscle/fat

which hypothalamic hormone stimulates TSH release

TRH (Thyroid Releasing Hormone)

what gland releases TSH

anterior pituitary

what gland is targeted by TSH

thyroid gland

what hormones does the thyroid gland produce

T3 and TD (thyroxine)

what is major effect/response of thyroid hormones

increase metabolism

what cells are targeted by thyroid hormones

most cells

what is the thyroid hormone pathway

hypothalamus - TRH - anterior pituitary - TSH - thyroid gland - TH (T3/T4) - most body cells

what homeostatic imbalance is related to thyroid hormone

Graves’ Disease

with what condition do we see sudden weight loss, increased heart rate, irregular beats, sweat, nervousness, and exophthalmos

Graves’ Disease

why do we see sudden weight loss with Graves Disease

because it affects the thyroid hormone that is responsible for increasing metabolism

what disease is autoimmune, occurs after an infection and is when an anti-body like protein mimics TSH and causes overstimulation of thyroid gland and hypersecretion of thyroid hormones

Graves’ Disease

are thyroid hormones amino-acid based or steroid based

amino-acid

how do thyroid hormones act like lipid-based hormones if they are amino acid based

lipid soluble and can enter cells directly without a membrane receptor

what mineral is required to make thyroid hormones

iodine

what hormonal imbalance occurs in Graves Disease

hyperthyroidism (hypersecretion of thyroid hormones)

what does the adrenocorticotropic hormone (ACTH) release

cortisol (stress hormone)

what is the follicle stimulating hormone responsible for

follicle growth and sperm production

what does the luteinizing hormone do

trigger ovulation

what does the prolactin hormone do

production of breast milk

what hormones are released from the posterior pituitary gland

oxytocin and anti-diuretic hormone (ADH)

list the endocrine glands

hypothalamus, pituitary gland, thyroid gland, parathyroid glands, thymus, adrenal glands, pancreas and ovary/testes

what are some functions of epithelial cells

absorption, secretion and maintaining boundaries

due to their regenerative capacity, epithelial cells undergo mitosis, increasing their risk for

cancer

some cancer types retain ability to synthesize a specific hormone so patient may initially seek medical attention because of hyper-secretion of that hormone which is called

secreting tumors

some cancer types lose ability to synthesize a specific hormone so patient may initially seek medical attention because of hypo-secretion of that hormone which is called

non-secreting tumor

with pituitary dwarfism, individuals also experience __ which results in not reaching sexual maturity (reproductive development)

decreased production of other pituitary hormones

how to treat too little GH (pituitary dwarfism)

synthetic growth hormone replacement therapy

more growth hormone is related to what signs/symptoms

increased fluid retention, diabetes, joint pain and risk of cancer

what transport mechanism is used to shuttle iodine molecules into the cell and keep its concentration significantly higher than in the blood

active transport

what hormone stimulates milk production

prolactin

what gland secretes prolactin

anterior pituitary

does prolactin cause milk production or milk release

milk production

where is oxytocin and ADH produced?

hypothalamus/posterior pituitary

what are the two target cell/organs for oxytocin

mammary glands and uterus

what are the major effects of oxytocin

contract to expel fetus and milk “let down”

oxytocin is released by a neural stimulus so what life events cause it to release and what is specifically triggered by

child birth (stretching of uterus) and breastfeeding (suckling)

what organ/cell does the ADH hormone target

kidney tublue cells

what are the major effects/responses related to ADH

increase water reabsorption which ultimately increases fluid in the blood, increasing the bp

what are homeostatic imbalances related to ADH

water retention because of less urine formation

what happens if ADH levels increase

less urine is produced

where are the parathyroid glands located

posterior of thyroid gland

what hormones do the parathyroid glands release

parathyroid hormone (PTH)

what stimulates PTH release

low blood calcium levels

what cell/organ does the PTH target

osteoclasts in bone, kidney tubules and intestines

how does PTH increase calcium levels

bone resorption, increased reabsorption by kidneys, and increased absorption by intestines

what are the three hormones of the adrenal cortex

aldosterone, cortisol and androgens

aldosterone, cortisol and androgens are amino-acid or lipid-based

lipid-based

adrenal gland is protected by a capsule but what would happen if cancerous tissue grows and bursts through?

metastasize

what is aldosterone’s main function

to increase sodium reabsorption

what follows sodium during aldosterone action

water

what is the overall effect of aldosterone if sodium and water increase

increased blood volume and blood pressure

what is the target cell/organ for aldosterone

kidney tubule cells

what stimulates aldosterone release

low blood pressure or low blood volume (detected by adrenal cortex)

what is cortisol’s major role

long term stress response

what is the pathway for aldosterone hormone

adrenal cortex - aldosterone - kidney tubule cells

what is the pathway for cortisol (glucocorticoid)

adrenal cortex - cortisol - most body cells

what is major effect/response of cortisol hormone

suppress immune system and mobilizes fat

what is a homeostatic imbalance related to cortisol

cushing’s syndrome

what condition is the most common medically induced from giving patients corticosteroids to treat autoimmune disease or prevent transplant injection

cushing

in cushing syndrome, the fat that is unused goes to other sites which is known as (sign)

buffalo hump

what are some common signs/symptoms associated with cushing syndrome

back pain, joint pain and allergies

cortisol is related to the release of

fat

androgens (pre testosterone and estrogen) are secreted from adrenal cortex and target what cells

some body cells

what are the major effects/responses of androgen hormone

female libido (sex drive) and axillary/pubic hair in females, little to no effect for males

androgens are converted into __ once released

testosterone and estrogen

what is the pathway for androgens

adrenal cortex - androgens - some body cells

what hormones are released by the adrenal medulla

catecholamines

what are catecholamines

epinephrine and norepinephrine

unlike the hormones released by the adrenal cortex that are lipid-based, the ones released from the adrenal medulla (catecholamines) are __ meaning shorter responses (secondary messengers/ cleared by kidneys)

amino-acid based

what nervous system division stimulates the adrenal medulla

sympathetic nervous system

What response do catecholamines produce?

fight or flight response (short term stress)

what are the major effects/responses of catecholamines

increased heart rate, respiratory rate and blood pressure

what cells/organs do catecholamines target

heart, respiratory muscles and vessels

what is pathway for catecholamines

adrenal medulla - catecholamines - heart, respiratory muscles and vessels

thymosin hormone is released by __ and targets the __ causing immune system activation

thymus; t cells

is the pancreas endocrine, exocrine or both

both because it secretes digestive enzymes onto digestive tract

what are the endocrine hormones of the pancreas

insulin and glucagon

what stimulates insulin release

high blood glucose

what cells secrete insulin

b cells

what is insulin’s major effect within the tissues vs. liver (how does it decrease blood glucose)?

increase glucose uptake for cell use and fat formation (long term); link glucose into glycogen molecules for storage (short term)

what is a homeostatic imbalance related to beta cells not producing enough insulin (hyposecretion)

type 1 diabetes

what stimulates glucagon release from the pancreas

low glucose levels