T1 l6:Adrenal Cortex - Hormones, Physiology

Question 1

what percentage is the medulla and the cortex of the adrenal gland

Answer 1

10% is the adrenal medulla and 90% outer adrenal cortex

Question 2

what is the main function of the adrenal medulla and cortex

Answer 2

The adrenal cortex is responsible for homeostasis (stress, sex, sodium, and glucose) response and the adrenal medulla is responsible for stress

Question 3

what from the diet is used to synthesize cortisol

Answer 3

Cholesterol

Question 4

give an example of a glucocorticoid

Answer 4

Cortisol

Question 5

give an example of the mineralocorticoids

Answer 5

Aldosterone

Question 6

what is the basic synthetic pathway

Answer 6

How from cholesterol you can derive cortisol , aldosterone and testosterone

Question 7

which area is cortisol made from

Answer 7

Zone fasciculata

Question 8

what zone is androgens synthesised from

Answer 8

Zone reticularis

Question 9

does the adrenal cortex secrete large volumes of sex hormones

Answer 9

no only small volumes such as testosterone and oestrogen

Question 10

what can occur to sex hormones with adrenal disorders

Answer 10

A large secretion of them

Question 11

How do you control the glucocorticoid secretion- give the flow chart and abbreviations of the chemicals

Answer 11

Hypothalamus: CRH

Anterior pituitary gland: ACTH

Adrenal cortex: Cortisol

Question 12

describe the secretion of ACTH and how it varies during the day

and the effect of prolonged stress

Answer 12

The secretion of ACTH is pulsatile:
peak in the early morning, at the time of waking
nadir in the middle of the night.

Increased secretion at time of prolonged stress.

Question 13

Cortisol secretion can be related to which cycle and what type of travel

Answer 13

The sleep wake cycle,

Long haul travels

Question 14

Describe the percentages of how glucocorticoids travel through the blood

Answer 14

10% free in the blood

15% albumin

75% corticosteroid binding globulin

Question 15

what [is pregnancy associated with

Answer 15

CBG-transcortin which increases the plasma protein concentrations

Question 16

how is adrenal steroids secreted when they are lipid soluble

Answer 16

They are glucuronidated in the liver to form water soluble forms which are excreted in the urine

Question 17

What are the effects of cortisol (5)

Answer 17

• Antagonizes the effects of insulin on cellular uptake of glucose
• Stimulates glycogenolysis
• Stimulates hepatic gluconeogenesis.
• Lipolysis
Vasoconstriction (in response to catecholamines)

Question 18

what does cortisol cause in excessive concentrations

Answer 18

Fat deposit in the face, trunk in the intrascapular region of the shoulders

Question 19

what periphery effects does cortisol have in the periphery

Answer 19

It inhibits protein synthesis results in amino acid uptake and protein synthesis - net loss of skeletal protein

Question 20

can glucocotricoids affect aldosterone receptors

Answer 20

Yes sometimes and also mineralocorticoid actions of glucocorticoids only apparent at high concentrations

Question 21

what psychological effect can glucocorticoids cause

Answer 21

Feelings of elation

Question 22

what is the stimulus for ACTH and corticosteroid release

Answer 22

Stress

Question 23

how do glucocorticoids affect the body’s defense systems at many levels

Answer 23

inhibit the cellular immune system:

They suppress the lymphoid tissue,

reduce antibody production
• They stabilize leucocyte membranes and reduce the release of proteolytic enzymes.
• They inhibit phospholipase A2 and reduce the synthesis of the inflammatory mediators.

Question 24

what does glucocorticoids do to your inflammatory response

Answer 24

They suppress their inflammatory response

Question 25

how is the inflammatory response suppressed

Answer 25

It removes the pain and decreases the immobilization induced by the oedema steroid-induced sedation also causes a lack of awareness of the severity of the situation.

Question 26

what causes the initial conversion of cholesterol into pregnenolone

Answer 26

ACTH

Question 27

what system influences the secretion of aldosterone

Answer 27

The renin-angiotensin system

Question 28

what other factors directly stimulate aldosterone

Answer 28

trauma, anxiety, hyperkalaemia and hyponatraemia and inhibited by atrial natriuretic peptide (ANP)

Question 29

what is the % of aldosterone that is protein bound

Answer 29

50%

Question 30

what occurs after intracellular receptor activation by aldosterone

Answer 30

expression of ion channels that transport sodium and potassium ions across the cell membrane.

Question 31

which tubule does aldosterone stimulate re-absorption from

Answer 31

distal tubule and collecting duct

Question 32

what is sodium exchanged for via aldosterone

Answer 32

potassium and H+ ions

Question 33

what other hormone does aldosterone work with to control blood volume and pressure

Answer 33

ADH

Question 34

what are adrenocorticosteroids used for

Answer 34

Replacement therapy & for their immunosuppressive/anti-inflame effects

Question 35

what conditions can adrenocorticoids affect

Answer 35

Arthritis Asthma Allergies Leukaemia

Question 36

what are mineralcorticoids used for

Answer 36

replacement therapy

Question 37

give an example of a mineralcorticoid drug

Answer 37

Fludrocortisol

Question 38

what are the adverse effects that are associated with the use of glucocorticoids

Answer 38

Steroid usage may suppress wound healing and may exacerbate infections due to their immunosuppresant effects. Long term use in children may cause inhibition of growth, and in adults may result in osteoporosis. The development of diabetes mellitus and other symptoms of Cushing’s syndrome also often accompanies steroid therapy. suppression of the hypothalamic-pituitary axis.

Question 39

what can occur due to chronic admin of exogenous glucocorticoids

Answer 39

suppression of ACTH secretion leading to atrophy of the adrenal cortex

Question 40

are steroids addictive or is there a misunderstanding

Answer 40

they are not addictive but : the adrenal cortex is unable to secrete endogenous hormones and the patient suffers an Addisonian crisis, which may be fatal. This consequence overcome by the gradual reduction of the dose of the exogenous steroid Other consequences of suppression of the anterior pituitary may include disturbances of sex hormone secretion resulting in symptoms such as menstrual disturbances

Question 41

what is the use of cortisol as a drug

Answer 41

is a natural glucocorticoid secreted by the adrenal cortex. It acts via specific intracellular glucocorticoid receptors to influence gene expression. Glucocorticoids are typically used for hormone replacement therapy, as anti-inflammatory agents and immunosuppressants. Hydrocortisone is the drug of choice for replacement therapy

Question 42

what is another name for cortisol

Answer 42

Hydrocortisone