Adrenocortical hormones Flashcards
1
Q
what is the central part of the adrenal gland
A
adrenal medulla
2
Q
adrenal medulla is regulated by
A
SNS
3
Q
major secretion of adrenal medulla and minor secretion
A
major: epinephrine
minor: norepinephrine
4
Q
what are the 3 zone of the adrenal cortex
A
zona reticular is: inner layer
zona fasciculatas: middle layer
zona glomerulosa: outer layer
5
Q
adrenal cortex secrete what
A
corticosteroid
6
Q
corticosteroid include how many type of hormones
A
30
7
Q
what is the principal mineralocorticoid
A
aldosterone
8
Q
aldosterone is secrete from
A
outer layer of adrenal cortex (zona glumerulosa)
9
Q
mineralcorticoids affect what
A
electrolyte Na, K ions in extracellular fluid
10
Q
does mineralocorticoid have weak or great glucocorticoid effect
A
weak
11
Q
what is the principal glucocorticoid
A
cortisol
12
Q
glucorticoid is secrete from
A
middle and inner layer of adrenal cortez
13
Q
which corticosteroid mainly increase glucose concentration in blood
A
glucorticoid
14
Q
abrogent play _ role as compared to estrogen and testosterone
A
minimal
15
Q
androgen is secrete from
A
middle and inner layer
16
Q
androgen as _ effect on body as testosterone
A
similar
17
Q
adrenocortical hormone are what type of compound
A
steroid-based
18
Q
adrenocortical hormones are mainly form from
A
cholesterol
19
Q
which type of protein contain cholesterol in blood
A
LDL
20
Q
LDL is absorbed from blood by
A
endocytosis through cell membrane
21
Q
the cell membrane from adrenal cortex promote what
A
endocytosis
22
Q
small amount of cholesterol is also synthesized where
A
in the cortical cell from acetyl-com
23
Q
cholesterol become what
A
pregnenolome
24
Q
T/F andrenocorticol hormone are hydrophobic
A
true which means they rely on carrier protein to get them around the circulation to the target tissue and get into ECF around cell
25
up _ % of cortisol bind with _ also know as _ or _
94 %, globulin, cortisol-binding globulin or transporting
26
about_ % is _ in blood
6, floating freely in blood
27
what does dynamic equilibrium means
cortisol is jumping on and off the carrier
28
up to _ of aldosterone binds with _
50, plasma protein
29
what is the effect of aldosterone on transport of Na and K
promote transport through renal tubular and in renal cortex and in renal collecting ducts
30
what are the cell responsible for the transport fo Na and k
principal cells
31
the transport of ions through renal tubular walls, cortex and collecting duct increase reabsorption of _ which means
Na, which means Na is conserved in ECF and decrease the loss of Na into urine
32
what happen when NA is reabsorbed
it increase K excretion into urine and caused water reabsorption by osmosis
33
what are the substances regulated by the kidney
Na, K, water, glucose, Cl, Ca and phosphate
34
explain the cellular mechanism of aldosterone action that increase sodium reabsorption
The lipid soluble aldosterone can diffuse readily into the principal epithelial cells,➔ binds with a receptor in the tubular cell, diffuses into the nucleus, ➔ Causes the formation Channel proteins and Na-K ATPase pump ➔now Na+ can be reabsorbed, K+
excreted.
35
where does channel protein inserted and what do they diffuse
nserted into luminal membrane of principal cell and result in rapid
diffusion of Na+ ions from lumen side, into cell cytoplasm
36
the lumen side is pointing where
inward where the kidney urine is located
37
where does Na and K are pump
at the basolateral membrane of renal principal cells
38
what structure are working together to pump Na and K
Na-K ATPase enzyme and membrane transport protein
39
where does the bas-lateral membrane face
outward to the interstitial fluid that is connected to the blood circulation
40
explain the effect on ECF volume and partial pressure from aldosterone
Aldosterone causes Na ions to be conserved ➔ tendency of increasing concentration of sodium ➔ simultaneous osmotic absorption of water by principal cells ➔ keep the concentration of Na constant ( very little rise ) in extracellular fluid ➔ absorption of water increases the volume of extracellular fluid ➔ increase blood pressure cause great increase of excretion of both water and salt (sodium chloride) from kidney at
hypertension ( called pressure diuresis ).
41
effect of aldosterone on sweat gland, salivary glad and intestinal absorption
- Aldosterone increase reabsorption of NaCl and secretion of K ions by principal cells to conserve body salt when water is secreted by sweat gland and salivary gland.
* Enhance NaCl absorption by intestine especially in the colon to prevent salt loss in the stools.
42
what happen with lack of aldosterone
Lack of Aldosterone causes loss of salt (Na) in urine ➔ decrease sodium-chloride in extracellular fluid and the volume of fluid ➔ great reduction of total volume of extracellular fluid (dehydration) and diminished cardiac output ➔ low blood pressure ➔ circulatory shock ➔ cause death in few days.
43
what happen if aldosterone is chronically low or defective due to a genetic mutation
the above sequence can be fatal. It can be prevented by providing medicine including aldosterone or other mineralocorticoids. It is an acute life-saver.
44
what happen if aldosterone is not working
it can cause gradual increase of K+ concentration in extracellular fluid and blood that is far above the normal which causes serious cardiac toxicity
45
what is hyperkalemia and what are the symptom
due to lack of aldosterone, when K concentration reaches to 60 to 100% above normal,weakness of heart contraction, arrhythmia (irregular heart beat).
46
What happens if there is a chronic excess of aldosterone?
excess aldosterone causes massive retention of Na+ and water reabsorption, which increases blood pressure and may trigger pressure diaresis.
* It causes excessive loss of K+ from extracellular fluid which can lead to a serious decrease of K+ concentration in blood. This is called hypokalemia.
* When K+ concentration fall below 1/2 to 1/3 normal it prevents transmission of normal action potential in the nerve which develops severe muscle weakness.
47
how can pressure dieresis can occurs
excess aldosterone causes massive retention of Na+ and water reabsorption, which increases blood pressure
48
what is hypokalemia
due to excess aldosterone, It causes excessive loss of K+ from extracellular fluid which can lead to a serious decrease of K+ concentration in blood.
49
how can muscle weakness can occurs if there is a problem with aldosterone regulation
du to chronic excess of aldosterone, When K+ concentration fall below 1/2 to 1/3 normal it prevents transmission of normal action potential in the nerve which develops severe muscle weakness.
50
what are the 4 factors that regulated aldosterone secretion (order of importance)
1. A small increase of K+ concentration in extracellular fluid will increase aldosterone secretion.
2. An increase of activity of renin-angiotensin system will increase aldosterone secretion
3a. An increase of Na+ concentration in extracellular fluid decreases aldosterone secretion.
3b. A 10 to 20% decrease of Na ion concentration can double aldosterone secretion. When adrenocoticotropic hormone 4. (ACTH) is secreted from anterior pituitary it causes aldosterone secretion. This is the most minor factor, however, if there is a total absence of
ACTH, like a genetic disease, it can significantly reduce aldosterone secretion.
51
what is gluconeogenesis and it's stimulate by what
Cortisol stimulates gluconeogenesis. This is the formation of glucose from amino acids and other substances by liver.
52
rate of gluconeo can increase as munch as
6 to 10 fold
53
what are the cascade of event by which cortisol increase gluconegenisis
Cortisol binds with receptor in the cytoplasm of hepatic cells ➔ diffuses into liver cell nucleus and activates DNA transcription ➔ formation of messenger RNA ➔ increase the enzymes needed to convert amino acids into glucose in hepatic (liver) cells.
54
cortisol mobilize amino acids from where
muscle
55
when the cortisol mobilize AA from muscle its what type of effect
catabolic
56
where does the amino acids goes when they leave the muscle
goes in the plasma. They fo from plasma to enter into the liver for gluconeogenesis
57
cortisol cause a _ in the utilization of glucose by cells
moderate decrease
58
why does cortisol cause a moderate decrease utilization of glucose by cells
because cortisol antagonize insulin andIt also depresses the oxidation of nicotinamide-adenine dinucleotide (NADH) to form NAD+ and NADH. Those must be oxidized to allow the use of glucose by cells. This is why cells can not effectively use glucose for energy
59
what is adrenal diabetes
If cortisol is in excess for long time, the glucose will accumulate in the blood and can be 50% more above normal.
60
what happen if cortisol is in excess for long time
the glucose will accumulate in the blood and can be 50% more above normal. This is called adrenal diabetes.
61
does cortisol allow the body to have carbs reserve
yes
62
glucose reserve can be used if what is present
epinephrine or glucagon
63
What is the effect of cortisol on protein metabolism?
* Cortisol reduces the protein stores in all body cell due to catabolic effects.
* Cortisol prevents amino acids from entering extra-hepatic cells (all the non-liver cells).
* Except, protein will increase in the liver because cortisol promotes uptake of amino acids into liver for gluconeogeneis, thus, cortisol promotes large amounts of liver enzymes that
are needed for gluconeogenesis.
* In the end, most proteins in muscles and other tissues are decreased by cortisol except for
liver proteins which are increased.
64
What is the effect of cortisol on fat metabolism?
Cortisol promotes mobilization of fatty acids from adipose tissue.
65
can excessive cortisol secretion make weight gain
Even though cortisol promotes 'fat burning', if there is excessive secretion of cortisol it may make a person hungry all the time and stimulate food intake. In this case weight gain may be observed if deposition of fat in tissues is greater than the rate of fat burning. Below, is a diagram summarizing the metabolic effect of cortisol.
66
what are the stage of inflammation
* Chemicals release from the damaged tissue cell and activate inflammation process. The chemicals include histamine, bradykinin, proteolytic enzyme, prostaglandins and leukotrienes.
* Blood flow is increased in the inflamed area (called erythema).
* Large amount of plasma leak out of the capillaries into damaged area because of the
increased capillary permeability.
* Leukocytes infiltrate through the area.
* At the end of inflammation, there is growth of fibrous tissue for the healing process.
67
what are the 2 basic anti-inflammatory effect of cortisol
It can block (attenuate) the early stage of inflammation or If inflammation has already begun, cortisol blocks most of factors that promote inflammation and causes rapid resolution of inflammation, and increases healing rate.
68
explain how cortisol can block the early stage of inflammation
Most of the proteolytic enzymes that cause inflammation are stored in lysosomes in the tissue cell. Cortisol can make the membrane of lysosome cell much more difficult to be ruptured ➔ greatly decrease the release of proteolytic enzymes into the inflamed area.
(b) Cortisol decreases the permeability of capillaries because of the reduced release of proteolytic enzymes ➔ reduce loss of plasma into damaged tissue area.
(c) Cortisol decreases the mobility of white blood cell into inflamed area ➔ decrease phagocytosis of the damaged tissues.
(d) Reduce the release of interleukin-1 from white blood cell ➔ suppresses the hypothalamic temperature control system ➔ lower the fever.
69
explain how cortisol can cause rapid resolution of inflammation and increase healing rate
a) Cortisol causes mobilization of amino acids and promote the use of them to repair damaged tissues, to increase glucose and fatty acids for cellular energy.
b) Plays an important role in combating rheumatoid arthritis, rheumatic fever, and acute glomerulonephritis.
70
what are some other effect of cortisol
reduce allergic reaction by reducing inflammation and the release of inflammatory product
decrease rate of lymphocyte and antibodies from lymphoid tissue which suppressed immunity of body -> makes cortisol and other glucocorticoids to be the most useful drugs for preventing immunological rejection of transplanted heart, kidney and other tissues.
increase production of red blood cells and probing healing of tissue
71
what can you do if you want to prevent immunological rejection of transplant tissue
use cortisol and other glucorticoids
72
secretion of cortisol is regulated by what
regulated by ACTH ( corticotropin or adrenocorticotropin ) which is secreted by anterior pituitary gland in response to corticotropin releasing hormone
73
how CRH is release
hypothalamus release corticotropin-releasing hormone (CRH) through hypophysial portal system in median eminence to anterior pituitary, which causes secretion of ACTH from anterior pituitary. ACTH acts on the adrenal cortex to synthesize adrenocortical hormones and cause them to be secreted.
74
explain how cortisol can be release in response to physical stress or tissue damage
Cause release of CRH to hypophysial portal system ➔ release of ACTH from anterior pituitary into blood, ➔ ACTH to adrenal cortex, ➔ release of cortisol, ➔ increase concentration of cortisol,
75
cortisol has a (negative/ positive) feedback effect on (hypothalamus/ ant. pituitary) to ( increase/decrease) formation of (CRH/ACTH)
Cortisol has a direct negative feedback effect on the hypothalamus to decrease formation of CRH.
76
cortisol had _ direct (negative/positive) feedback on the (hypothalamus/pituitary gland) to (increase/decrease) the formation of (CRH/ACTH)
Cortisol also has a direct negative feedback on the anterior pituitary gland to decrease the formation of ACTH.
77
what can cause immediate increase in ACTH secretion by anterior pituitary gland
stress: pain, trauma, infection, intense heat or cold, injection of norepinephrine, surgery, injection of necrotizing chemical beneath skin, debilitating disease, psychological
78
if there is an increase in ACTH secretion due to stress there is a (increase/decrease) rate of secretion of cortisol by adrenal cortex
increase
79
what is hypoadrenalism
primary adrenal insufficiency. It is primary because the adrenal gland does not make enough of the adrenal hormones. This could be due to atrophy (small size), loss, or injury to the adrenal glands. Can be caused most often by autoimmune disease, but also by infections like tuberculosis or cancer that destroys the glands. Can be a side effect of chemotherapy treatments.
80
exemple of hypoadrenalism
addison's disease
81
what is secondary adrenal insufficiency
caused by a defective pituitary gland which doesn't secrete enough ACTH. It is more common than Addison's disease. Causes vary, could be genetic mutation, birth defect, infection of pituitary, or some problem with hypothalamus or CRH.
82
what happen if the primary or secondary adrenal insufficiencies are chronic : lack of aldosterone
lack of mineralcorticoids such as aldosterone, the sodium ions are excreted into urine, which causes loss of water by osmosis. If its untreated blood pressure and dehydration can be fatal. Also, there is compensatory increase in potassium in the blood that can lead to hyperkalemia.
83
what happen if the primary or secondary adrenal insufficiencies are chronic : lack of aldosterone: lack of cortisol
If there is a lack of glucocorticoids such as cortisol, then in between it is difficult to maintain blood glucose levels since gluconeogenesis is impaired. Stress of infection can be deadly because cortisol normally suppresses inflammation and promotes healing.
84
what happen if the primary or secondary adrenal insufficiencies are chronic : lack of aldosterone: lack of catecholamine
If the medulla is defective, then the lack of catecholamines such as adrenaline will alter mood and make hypoglycemia more likely. Adrenaline is able to mobilize glucose in times of need, so lacking it is dangerous.
85
what happen if melanin deposition increased
Melanin has various functions including skin pigmentation. Because cortisol is low, the pituitary over produces ACTH, which also provides more MSH (melanin stimulating hormone) which gets unevenly distributed in skin, creating a spotty appearance in the skin. This would not occur if the patient has an ACTH deficiency.
86
what are the treatment for adrenal insufficiency
* Daily supplement with synthetic mineralcorticoids and glucocorticoids
* In cases of trauma, extra glucocorticoids must be given
* Corticosteroids given to suppress the immune system if it is autoimmune in nature
* allergic reactions may need more medication to control inflammation
87
Addison disease is a primary or secondary adrenal insufiency
primary
88
exemple of hyperadrenalism
Cushing's syndrome or Conn's syndrome
89
what is hyperadrenalism
It is defined by hypersecretion of adrenal hormones. The cause may be adenoma tumor which produces adrenal hormones out of control. May be in glands or elsewhere in body. Or, an abnormal function of the hypothalamus-pituitary axis that makes more ACTH than needed.
90
effect of excessive glucocorticoid (cortisol):
high blood sugar leading to pituitary diabetes, and loss of protein from muscle, and redistribution of fat into the torso
91
effect of excessive androgen
over masculinizing effect
