Adrenal gland

Question 1

Where are the adrenal glands located?

Answer 1

Situated superiorly over the medial and superior aspect of the kidney

Question 2

Which hormones are secreted by the adrenal glands?

Answer 2

Secretes steroids and catecholamine hormones into systemic circulation

Question 3

what shape is the right adrenal gland?

Answer 3

Pyramidal shape, contracting with the semi-lunar shape of the left gland

Question 4

Which type of fascia encloses the adrenal glands?

Answer 4

Perinephric fascia

Question 5

What is the anatomical relationship between the spleen and adrenal glands?

Answer 5

The left adrenal gland resides inferior to the spleen

Question 6

Where does the left adrenal vein drain into?

Answer 6

Traverses into the renal vein

Question 7

Where does the right adrenal vein drain into?

Answer 7

inferior vena cava

Question 8

How many arteriole branches supply each adrenal gland?

Answer 8

57 arteriole branches

Question 9

What is the outer adrenal gland called?

Answer 9

Cortex

Question 10

What is the inner adrenal gland?

Answer 10

Medulla

Question 11

What are the three layers of the adrenal cortex?

Answer 11

Zona glomerulosa, zona fasciata, zona reticularis

Question 12

Which hormones are secreted from the Zona glomerulsosa?

Answer 12

Aldosterone (mineralcorticoids)

Question 13

Which hormone is secreted from the zone fasciulata?

Answer 13

Cortisol

Small proportions of androgens

Question 14

Which hormone is secreted by the zone reticularis?

Answer 14

Androgens and oestrogens

Smaller proportions of corticosteroids

Question 15

Which cells are located within the adrenal medulla?

Answer 15

Chromaffin cells

Question 16

Which hormones are secreted by the adrenal medulla?

Answer 16

Adrenaline and noradrenaline

Question 17

Which molecule are steroids derived from?

Answer 17

Cholesterol

Question 18

How many carbon atoms are present in cholesterol?

Answer 18

27

Question 19

What is the structure of cholesterol?

Answer 19

Cyclic rings

Question 20

How is cholesterol converted into pregnenolone?

Answer 20

Side chain cleavage (p450scc)

Question 21

How is pregvnenlone converted into progesterone?

Answer 21

3-beta-hydroxy steroid dehydrogenase

Question 22

What is the next step for progesterone –> aldosterone synthesis?

Answer 22

21-hydroxylase hydroxylates C21, converting progesterone into 11-dexoycorticosterone

Question 23

How is 11-deoxycorticosterone converted into aldosterone?

Answer 23

11-hydroxylase into corticosterone

Question 24

How is corticosterone converted into aldosterone?

Answer 24

18-hydroxylase

Question 25

Describe the pathway of molecules for cholesterol to cortisol synthesis?

Answer 25

Cholesterol --> Pregnenolone -->Progesterone --> 17-hydroxy-progesterone --> 11-deoxycortisol --> cortisol

Question 26

Which enzymes are involved with cortisol synthesis?

Answer 26

17-hydroxylase 21-hydroxylase 11-hydroxylase

Question 27

Which hormone influences the synthesis of cortisol?

Answer 27

ACTH

Question 28

How is cortisol predominantly transported within the body?

Answer 28

Corticosteroid binding globulin

Question 29

Which transport protein transports 15% of cortisol?

Answer 29

Albumin

Question 30

Which form is cortisol active?

Answer 30

Unbound form (10%)

Question 31

What is the function of aldosterone?

Answer 31

Stimulates Na+ reabsorption in the distal convoluted tubule and cortical collecting duct. Essential for kidneys, sweat glands, gastric glands and colon. Stimulates K+ and H+ secretion in the distal convoluted tubule and cortical collecting duct; alternating pH regulation of the blood.

Question 32

What effect does aldosterone have on potassium and hydrogen ions?

Answer 32

Stimulates potassium and hydrogen ion secretion in the distal convoluted tubule and cortical collecting duct

Question 33

What is the mechanism of aldosterone?

Answer 33

permeable, binding to intracellular receptors. Hormone-receptor complex traverses to the nucleus, attaching to the DNA, activating target genes. Hormone-receptor complex behaves as a transcription factor, binding to promoter regions. Transcription factor results in mRNA transcription, and translation of ion pumps & enzymes. ATPase pump on the basolateral membrane pumps sodium into circulation. Aldosterone stimulates the synthesis of sodium ion channels in the apical membrane.

Question 34

How does the glomerulus receive blood?

Answer 34

Afferent arteriole within the nephron

Question 35

Which arteriole carries blood away from the glomerulus?

Answer 35

Efferent arteriole

Question 36

Where are the juxtaglomerular cells located?

Answer 36

Lining the ascending limb of the loop of Henle, and the distal convoluted tubule, exposed to the afferent arteriole

Question 37

What is the function of the juxta-glomerular cells?

Answer 37

Secretes renin

Question 38

Which region of cells lies adjacent to the JG cells?

Answer 38

Macula densa

Question 39

What is the function of the macula densa?

Answer 39

Responds to changes in sodium ion concentration.

Question 40

Which receptors are located on JG cells and afferent arteriole?

Answer 40

beta-1 adrenergic, responds to sympathetic stimulation

Question 41

Which three factors contribute to renin release?

Answer 41

Decreased renal perfusion pressure Increased renal sympathetic activity Decreased sodium load

Question 42

Which hormone is secreted by the liver, which influences aldosterone synthesis?

Answer 42

Angiotensinogen

Question 43

What effect does renin have on the renin-angiotensin system?

Answer 43

Renin converts angiotensinogen into angiotensin I

Question 44

How is angiotensin-1 converted into angiotensin-2?

Answer 44

Angiotensin converting enzymes (ACE)

Question 45

What effect does angiotensin II have on the zone glomerulosa?

Answer 45

Stimulates the production of aldosterone

Question 46

What effect does an increase potassium concentration have on angiotensin?

Answer 46

Increases angiotensin concentration

Question 47

What effect does angiotensin -II have on vasculature?

Answer 47

Vasoconstrictor

Question 48

Which hormone has a permissive effect (enhancing) On the renin-angiotensin system?

Answer 48

Corticotrophin

Question 49

What is cortisol typically associated with?

Answer 49

Stress hormone

Question 50

Where is cortisol made?

Answer 50

Zone fasciculate of the adrenal cortex

Question 51

What metabolic effects are exerted by cortisol?

Answer 51

Stimulates peripheral protein catabolism, Hepatic gluconeogenesis Enhances effects of glucagon and catecholamines Stimulates glycogenolysis Fat lipolysis of adipose tissue Overall effect: Increases blood glucose concentration

Question 52

What effect does cortisol have on mineralcorticoid receptors?

Answer 52

Behaves as aldosterone, assets with water and sodium ion retention

Question 53

How is cortisol converted into cortisone?

Answer 53

IIB-Hydroxysteroid dehydrogenase 2, removes cortisol to reduce interference with mineralcorticoid receptors

Question 54

What is the pattern of secretion of cortisol?

Answer 54

Diurnal rhythms

Question 55

What is Addison's disease?

Answer 55

Inadequate secretion of cortisol from adrenal cortex

Question 56

What are the main causes of Addison's disease in the UK?

Answer 56

Autoimmune disease

Question 57

What are the main two main causes of Addison's disease?

Answer 57

TB and autoimmune disease

Question 58

How does TB cause Addison's disease?

Answer 58

TB in the adrenal gland, reduces the cells that consist the zone fasciculate, therefore reducing secretion of cortisol, according to negative feedback system, this would elevate levels of ACTH from the anterior pituitary gland

Question 59

Which hormonal levels increase in Addison's?

Answer 59

CRH ACTH MSH

Question 60

What are the clinical effects of Addison's disease?

Answer 60

``` Hypoglycaemia Low blood pressure weakness Bronze discolouration Hyponatremia Hyperkalaemia Metabolic acidosis Autoimmune vitillog Infertility ```

Question 61

Why is there bronze pallor and increase pigmentation in Addisons?

Answer 61

Pro-opiomelanocortin precursor protein that is cleaved to form small peptides, including ACTH and MSH

Question 62

What is MSH?

Answer 62

Melanin stimulating hormone

Question 63

What are the treatments of Addison's disease?

Answer 63

Glucose/dextrose intravenous solution | Steroid IV replacement therapy (Hydroxycortisone)

Question 64

What tests are conducted in regards to the management of Addison's?

Answer 64

Measure urea electrolytes Measure blood pressure Short synacthen test, ACTH, measure cortisol level afterwards

Question 65

When should cortisol level measurements take place?

Answer 65

8am, when cortisol levels are highest

Question 66

What is Cushing's syndrome?

Answer 66

Concerned with elevated levels of cortisol, primarily caused by an adrenal adenoma

Question 67

What are the main effects of Cushing's?

Answer 67

``` Impaired glucose tolerance Hypertension Hyperglycaemia Proximal myopathy (muscle weakness) Mental changes Skin changes Centripetal obesity ```

Question 68

What are the common causations of Cushing's?

Answer 68

Oral consumption of steroids | Ectopic ACTH secretion (Lung cancer)

Question 69

Where does the adrenal medulla derive from?

Answer 69

Ecotdermal neural crest

Question 70

Which amino acid is the precursor for adrenaline and noradrenaline

Answer 70

Tyrosine

Question 71

What stimulates the release of catecholamines in cytoplasmic granules?

Answer 71

Acetylcholine

Question 72

What molecules are bound to noradrenaline and adrenaline?

Answer 72

Albumin

Question 73

Which hepatic enzymes degrade catecholamines?

Answer 73

Monoamine oxidase | Catechol-o-methyl transferase