Unit 3: adrenal glands Flashcards
small, triangular glands located on top of each kidney. produce hormones for metabolism, immune function, bp reg, and stress response
adrenal glands
secretes aldosterone, adrenal androgens, norep, epi, cortisol
adrenal glands
Consist of an outer adrenal cortex and an
inner adrenal medulla that function as
separate glands
adrenal glands
neural tissue and
secretes epinephrine and norep in response to sympathetic neural stimulation
adrenal medulla
glandular epithelium
and secretes steroid hormones in response to
ACTH
adrenal cortex
3 layers of adrenal cortex
zona glomerulosa, zona
fasciculata, and zona reticularis
produce cortisol, aldosterone, and androgens
cortex
secretes norep and epi
adrenal medulla
glucocorticoids. reg metabolism, immune response, and stress
cortisol
mineralocorticoids. reg BP and electrolyte balance
aldosterone
precursor hormone converted to sex hormones
androgens
produced by cortex. helps reg BP by controlling sodiu and potassium levels.
aldosterone
secretion stim by renin-angiotensin-aldosterone-system (RAAS) and elevated potassium levels and ACTH
aldosterone
responsible for secretion of substances like enzymes, horms, musuc, and sweat. forms functions of endo and exo glands
glandular epithelium
what makes ACTH
anterior pit
Hypothalamus (CRH) tells ant pit to make …
ACTH
outer layer. produces mineralocorticoids. regulates electrolytes and fluid balance by Na retention and K excretion (helps control BP)
zona glomerulosa
stim by RAAS and increase K levels
zona glomerulosa
middle layer. produce glucocorticoids. involved in metabolism regulation, stress response, and reduce inflammation. stim by ACTH from pit gland
zona fasciculata
inner layer. produce androgen. contributes to secondary sexual characteristics and has minor effects on metabolism. stim by ACTH
zona reticularis
what are the specific hormones produced in the zonas
G- salt
F- sugar
R- sex
the adrenal cortex Secretes hormones made from cholesterol;
called
corticosteroids
3 categories of corticosteroids
-mineralocorticoids
-glucocorticoids
-adrenal androgens
from the zona glomerulosa
regulate Na + and K + balance.
1) Example: aldosterone
mineralocorticoids
from the zona fasciculata
regulate glucose metabolism.
1) Example: cortisol
glucocorticoids
from the zona reticularis are
weak sex hormones that supplement those made
in the gonads.
adrenal androgens
increase blood glucose and BP
cortisol
why is an increase in BP and blood glucose beneficial
more blood in the right places
store glucose in liver
glycogen
glycogen broken down into glucose, used for energy
-increase glucose in blood
glycogenolysis
what prevent t-cell production. you dont want t-cells during stress and inflammation. we want balance
cortisol
a. Stimulates protein degradation
b. Stimulates gluconeogenesis and inhibits
glucose utilization to raise blood glucose levels
c. Stimulates lipolysis
function of cortisol (hydrocortisone)
used
medically to suppress immune response
and inhibit inflammation; can have many
negative side effects
exogenous glucocorticoids
protein broken down into smaller peptides or amino acids
protein degration
glucose prod in liver
-build new sugars
-lipid metabolise
gluconeogenesis
side effects of exogenous glucocorticoids
-immune suppression
-osteoperosis
-metabolic changes
Activated with sympathetic response
epi and norep
Have effects similar to sympathetic
innervation but lasting 10 times longer
epi and norep
effects of epi and norep in adrenal medulla during fight/flight
Increase cardiac output, respiratory
rate, and mental alertness;
dilate coronary blood vessels; elevate metabolic rates
Stress increases secretion
acth
secretion of — results in increased glucocorticoid release
acth
what are the stress hormones released in adrenal gland
glucocorticoids,
epinephrine, and CRH
what are the key players in GAS (general adaptation syndrome)
glucocorticoids,
epinephrine, and CRH
Good for proper recovery after stress, such as an
illness or trauma
general adaptation syndrome
Cortisol helps inhibit the immune system so it does
not overrespond
general adaptation syndrome
Chronic stress leads to
increase risk of illness
— may act on higher brain
regions, contributing to depression
and anxiety and memory
cortisol
By stimulating the liver to release
glucose…
insulin receptors may
become resistant, making it harder
to treat people with diabetes.
3 stages physiological response to stress that describes how the body reacts to stressors over time
GAS
stages of gas
alarm, resistance, exhaustion
activates the
adrenal glands
-initial reaction
-release cortisol and epi
-fight/flight
alarm reaction
readjustments in response
-cortisol levels remain elevated and body shifts to sustained coping mechanisms.
-body energy reserved to cope w/ stress
-get sick: day 2 is bad. day 4 is better
resistance
may lead to sickness or death
-get sick for long time= organ failure
exhaustion
1) Stimulates growth of adrenal glands
2) Atrophy of lymphatic tissue of spleen,
lymph nodes, and thymus
3) Formation of bleeding peptic ulcers
gas effects
results from chronically high
levels of glucocorticoids
cushings syndrome
causes lipolysis and a redistribution of fat that can
produce a “buffalo hump” (a fatty deposit between the
shoulders and the below the back of the neck), a
“moon” (round) face, and other symptoms.
cushings syndrome
most commonly occurs when a person takes
sustained high doses of glucocorticoid medicines
cushings syndrome
glucocorticoid meds
prednisone, prednisolone, and dexamethasone
- asthma, copd, rheumatoid arthritis
cushings syndrome can also be produced by
a pituitary tumor that secretes excessive ACTH
* a benign tumor of the adrenal that secretes excessive
cortisol without requiring ACTH stimulation
caused by inadequate secretion of corticosteroids
addisons disease (adrenal insufficiency)
Inadequate cortisol produces
hypoglycemia (low
blood glucose)
inadequate aldosterone produces
sodium and potassium imbalances, dehydration, and
dangerously low blood pressure
Primary adrenal insufficiency results from
autoimmune destruction of the adrenal cortex.
butterfly shaped endo gland located anterior of trachea and just below larynx (voice box)
thyroid gland
Has two lobes on
either side of the
trachea,
connected by the
isthmus
thyroid gland
func in metabolic reg, growth, thermoregulation, produce T3 and T4 and calcitonin
thyroid gland
cell type of thyroid gland
-follicular
-parafollicular
produce 2 main types of thyroid horm
follicular cells
produce calcitonion
parafollicular
horm involved in calcium reg.
-decrease calcium levels by promoting calcium storage in bones.
calcitonin
what is needed to produce thyroid horm
iodine
enzymes within the colloid generate
t4= thyroxine
t3= triiodothyronine
main horm produces.
-less active form, more abundant
-converts t3 in peripheral tissue
t4- thyroxine
active form. more potent, less abundant
-body temp
t3
follicle cells secrete
T 4 (tetraiodothyronine or
thyroxine)
T 3 (triiodothyronine)
a. Stimulates protein synthesis
b. Promotes maturation of the
nervous system
c. Increases rates of cellular
respiration
d. Elevates basal metabolic rate
action of thyroid horm
what creates heat in thyroid horm
increase cell resp and elevated basal metabolic rate
when you get the flu, what horm are secreted?
CRH, epi, cortisol, thyroid
because fever
Made by the parafollicular
cells
calcitonin
btwn follicles and produce calcitonin
parafollicular cells
Inhibits dissolution of calcium
from bone and stimulates
excretion of calcium in the
kidneys to lower blood
calcium levels
calcitonin
what is endemic goiter caused by
low iodine
Generally 4 glands embedded
in the back of the thyroid
gland
parathyroid glands
Secrete
parathyroid
hormone (PTH)
parathyroid glands
Hormone
promotes a rise
in blood calcium
by acting on
bones, kidneys,
and intestine
parathyroid
hormone (PTH)
