Endocrine Part 3 Flashcards
what is produced by the adrenal cortex and the adrenal medulla
The adrenal cortex is composed of the zona glomerulosa, zona fasciculata, and zona reticularis, each producing distinct hormones, while the adrenal medulla produces catecholamines
list the 3 outer layers of the adrenal gland starting from the outside the medulla
- zona glomerulosa
- zona fasciculata
- zona reticulus
with the 3 layers of the adrenal gland: zona glomerulosa, zona fasciculata, zona reticulus, what are the hormones that they produce and their function?
glomerulusa: produces mineralocorticoids, example is aldosterone, sodium and water retention of the kidneys
fascuculata: produces glutocorticoids, eg cortisol, sugar/glucose metabolism, increases energy supply
reticularis: produces androgens like DHEA and Androstenedione, has sex functions
produces androgens like DHEA and Androstenedione
a. zona glomerulosa
b. zona fasciculata
c. zona reticularis
zona reticularis
aldosterone (mineralcorticoid), cortisol (glucocorticoids), and adrenal adrogens all come from _____, which is converted from _______.
a. protein hormones, prehormone
b. steroids, cholesterol
c. progesterone, cholesterol
d. chondrocytes, fibroblasts
cholesterol is converted to progesterone, then progesterone makes mineralcorticoids, glucocorticoids, and adrenal androgens, which are made based on the body’s needs
Which of the following is a general property of adrenal hormones?
a) They are all derived from amino acids
b) They primarily regulate digestive functions
c) Their synthesis is independent of enzymatic activity
d) Their secretion is controlled by the hypothalamic-pituitary-adrenal (HPA) axis and respond to various stimuli such as stress and changes in electrolyte balance
heir secretion is controlled by the hypothalamic-pituitary-adrenal (HPA) axis and respond to various stimuli such as stress and changes in electrolyte balance
Adrenal hormone secretion is regulated by the HPA axis and responds to stress and electrolyte balance changes
how does aldosterone affect Na+, K+, and H+ levels in the body? and why does this happen?
- increases Na+ reabsorption with water in the blood (because to retain water, Na+ must occur first
- increased K+ secretion by the kidney
- increased H+ secretion by the kidney
(K+ and H+ secretion increases due to loss of these ions in urine)
Which of the following statements BEST describes the mechanism of aldosterone action and the channels involved?
a) Aldosterone directly activates ion channels in the kidney tubules, leading to immediate sodium and potassium transport without affecting gene transcription
b) Aldosterone binds to intracellular receptors, leading to altered gene transcription and increased synthesis of epithelial sodium channels (ENaC) and Na+/K+ ATPase pumps
c) Aldosterone increases water reabsorption by directly stimulating aquaporin channels in the collecting duct without involving gene transcription
d) Aldosterone solely affects potassium secretion by inhibiting the Na+/K+ ATPase pump, without any impact on sodium channels or gene transcription
he correct answer is b) Aldosterone binds to intracellular receptors, leading to altered gene transcription and increased synthesis of epithelial sodium channels (ENaC) and Na+/K+ ATPase pumps @11, @12. Aldosterone exerts its effects by binding to a mineralocorticoid receptor inside the cell, which then acts as a transcription factor to increase the production of specific proteins, including ENaC and Na+/K+ ATPase pumps 2, 3. These proteins are crucial for sodium reabsorption and potassium secretion in the kidney 4, 1.
(Na+ gets reabsorbed, K+ leaves in urine)
Option a) is incorrect because aldosterone’s primary mechanism involves gene transcription, not direct channel activation 2.
Option c) is incorrect as aldosterone’s primary action is on sodium channels, and water reabsorption is secondary to sodium reabsorption 4, 1. While aquaporins are involved in water reabsorption, aldosterone’s main effect isn’t a direct influence on aquaporin channels 4.
Option d) is incorrect because aldosterone impacts both sodium and potassium transport and acts via gene transcription 4, 2.
Which of the following conditions primarily triggers aldosterone secretion? and what is the net result?
a) High blood pressure, high ECF volume, and high Na+ in blood.
b) Low blood pressure, low ECF volume, and low Na+ in blood.
c) High blood pressure, low ECF volume, and high Na+ in blood.
d) Low blood pressure, high ECF volume, and high Na+ in blood.
Low blood pressure, low ECF volume, and low Na⁺ in blood.
Aldosterone is mainly triggered when your body needs to raise blood pressure and conserve sodium. The main signals that stimulate its release are:
Which of the following physiological functions is primarily regulated by aldosterone?
a) Blood glucose levels
b) Sodium and potassium balance
c) Immune response
d) Sleep-wake cycle
Aldosterone primarily regulates sodium and potassium balance by increasing sodium reabsorption and potassium secretion in the kidneys
which of the following is true for aldosterone?
1. its a steroid hormone
2. its a protein hormone
3. it is primarily under the control of the anterior pituitary hormone
4. it is primarily not under the control of the anterior pituitary hormone
the correct options are:
- aldosterone is a steroid hormone that is not primarily under the control of the anterior pituitary hormone
Angiotensin II and high potassium ion levels both stimulate the secretion of which hormone from the adrenal cortex?
a) Cortisol, leading to increased blood glucose levels.
b) Aldosterone, leading to increased sodium reabsorption and potassium secretion .
c) Androgens, leading to the development of secondary sexual characteristics.
d) Epinephrine, leading to increased heart rate and blood pressure.
Aldosterone, leading to increased sodium reabsorption and potassium secretion .
Which of the following mechanisms primarily regulates cortisol secretion?
a) Direct innervation by the sympathetic nervous system.
b) A positive feedback loop involving ACTH
c) The renin-angiotensin system
d) The hypothalamic-pituitary-adrenal (HPA) axis, involving CRH and ACTH
Cortisol secretion is mainly controlled by the HPA axis, involving CRH and ACTH
Which of the following statements about cortisol is incorrect?
A. Cortisol increases hepatic gluconeogenesis and protein catabolism during stress
B. Cortisol enhances immune system activity by promoting lymphocyte proliferation
C. Cortisol decreases peripheral glucose utilization and increases blood glucose
D. Cortisol has permissive effects on catecholamines to help maintain blood pressure
E. Cortisol increases glucose availability in the CNS
Correct Answer: B
Rationale: Cortisol suppresses the immune system—it reduces lymphocyte numbers, shrinks lymph nodes, and decreases production of inflammatory mediators. It does not promote lymphocyte proliferation; in fact, it increases susceptibility to infections
what is the general function or cortisol?
a. vitamin D metabolism
b. affects the metabolism of glucose (gluconeogenesis)
c. it affects the metabolism of glucose (glucocorticoids)
it affects the metabolism of glucose (glucocorticoids)
how does cortisol react to stress conditions? (eg trauma, physical stress, emotional stress)
cortisol is secreted during stressful conditions to protect the body under stress conditions
- cortisol protects the body from hypoglycemia (low sugar levels) and prevent low blood glucose (glutocorticoids) in order for the body to have lots of energy to deal with stress
cortisol also helps with non-stressful conditions
how does the endocrine system respond to stress?
- more cortisol released from the adrenal cortex
- epinephrine and norephinephrine *from the adrenal medulla)
what does it mean for cortisol to have permissive action on ephinephrine and norephinephrine?
it means that cortisol enables ephinephrine and NE to exert its full effects on target tissues, this helps maintain blood pressure at a normal level
how does cortisol affect metabolism of glucose, proteins, and fats?
cortisol increase protein and fat breakdown
cortisol increases glucose breakdown by promoting gluconeogenesis and regulates how our bodies use energy for energy it also regulates glucose levels in the body
cortisol also increase blood glucose levels by promoting gluconeogenesis in the liver to reduce the body’s sensitivity to insulin
how does cortisol effect the immune system?
cortisol puts a break on the immune system
Cortisol suppresses the immune system—it reduces lymphocyte numbers, shrinks lymph nodes, and decreases production of inflammatory mediators. It does not promote lymphocyte proliferation; in fact, it increases susceptibility to infections
why does cortisol promote gluconeogenesis?
it is used to prevent hypoglycemia (catabolism) to manafe stress, raising blood sugar levels
a disease due to hyposecretion of cortisol, low acth, low aldosterone decreased blood glucose and increaed hyperpigmentation
a. cushings syndrome
b. conns syndrome
c. addisons disease
d. secondary adrenal insufficiency
too little cortisol and aldosterone cause addisons disease
your patient has hypersecretion of cortisol, they have weight gain, muscle weakness, hyperglycemia, decreased resistance to infection, buffalo humps, and moon face
a. cushings syndrome
b. conns syndrome
c. addisons disease
d. secondary adrenal insufficiency
cushings disease
a disease involved in hyposecretion of adolsterone and cortisol. causes hypotension, metabolic acidosis, hyperkalemia
a. cushings syndrome
b. conns syndrome
c. addisons disease
d. secondary adrenal insufficiency
addisons disease
