Physiology 2

Question 1

What is the effect of prolonged insulin on insulin receptors?

Answer 1

Downregulates

Question 2

What are the two clinical pictures of an insulinoma?

Answer 2

Hypoglycemia initially, then hyperglycemia later on d/t downregulation of the receptors

Question 3

What is the serum protein that binds to cortisol?

Answer 3

Transcortin

Question 4

What is the effect of estrogen on cortisol binding globulin?

Answer 4

Decreases

Question 5

What is the most important amino acid in producing a glucogenic response?

Answer 5

Alanine***

Question 6

What is the effect of cortisol in the liver? Muscle? Adipose tissue?

Answer 6

Liver = glycogen synthesis

Other - glycogenolysis

Question 7

How does cortisol decrease the inflammatory response?

Answer 7

Inhibits phospholipase A2

Question 8

What are the three products of COX enzymes?

Answer 8

• Prostacyclins
• Prostaglandins
• Thromboxanes

Question 9

What is the enzyme that produce leukotrienes? What is the substrate for this?

Answer 9

Lipoxygenase

Arachidonic acid

Question 10

Why may NSAIDs exacerbate asthma attacks?

Answer 10

Block COX will shunt to lipoxygenase pathway

Question 11

What nonsteroid hormone has intranuclear transduction?

Answer 11

Thyroxine

Question 12

What is the major hormone that is needed for neurological development in the newborn?

Answer 12

Thyroxine

Question 13

What is the most potent glucocorticoid?

Answer 13

Dexamethasone

Question 14

What is the most selective mineralocorticoid?

Answer 14

Fludrocortisone

Question 15

Why is it that low leads to lower insulin levels?

Answer 15

Lack of depolarization in the beta cells of the pancreas

Question 16

Why is it that cushing’s causes peptic ulcers?

Answer 16

Lower amounts of COX-1

Question 17

Why does Cushing’s cause myopathy?

Answer 17

Loss of muscle glycogen and protein d/t gluconeogenesis

Question 18

What are the three major drugs that inhibit the adrenal cortex?

Answer 18

• Ketoconazole
• Aminoglutethimide (aromatase inhibitor)
• Spironolactone

Question 19

What is the MOA of ketoconazole in terms of adrenal function?

Answer 19

Inhibits desmolase

Question 20

What are the three major steroids that have mineralocorticoid effects?

Answer 20

• Aldosterone
• Fludrocortisone
• Deoxycorticosterone

Question 21

What are the two major lethal side effects of corticosteroids?

Answer 21

CHF

Hypokalemia

Question 22

What is the major breakdown product of testosterone / estrogen, androsterone etc? When are these elevated?

Answer 22

Ketosteroids–Cushing’s, testicular CA, PCOS

Question 23

What is Cushing’s disease vs syndrome?

Answer 23

Disease is primary pituitary adenoma

Syndrome = 2/2 to some other cause

Question 24

Which is active: cortisol or cortisone?

Answer 24

Cortisol is active

Question 25

What is the function of HSD-1? HSD2?

Answer 25

HSD-2 is only in the nephrons, and inactivates cortisol, to prevent action on the mineralocorticoid receptors

Question 26

What is the issue with licorice?

Answer 26

Inhibits 11-HSB 2

Question 27

What happens to WBCs with cushing's and addison's?

Answer 27

Eosinophilia in addison's | Eosinopenia in cushing's

Question 28

What is the classic metabolic disturbance with Cushing's?

Answer 28

Hypokalemic alkalosis

Question 29

What are the classic cancers that cause Cushing's?

Answer 29

``` Thymomas Oat cell CA Pheo Islet cell tumors Carcinoid tumors ``` (TOPIC)

Question 30

What is Conn's syndrome?

Answer 30

Adenoma or hyperplasia of the zona glomerulosa

Question 31

What are the cells that produce renin?

Answer 31

JG cells

Question 32

What does the macula densa sense, and do?

Answer 32

Senses renal flow, and will decrease JG cells from releasing Renin

Question 33

What are the two main immediate stimulants of aldosterone secretion?

Answer 33

Hyperkalemia and ANG II

Question 34

What happens to renin with CHF?

Answer 34

Increases

Question 35

What are the receptors on JG cells?

Answer 35

Beta 1 receptors

Question 36

How does hyperthyroidism cause HTN?

Answer 36

Y is a part of thyroid hormone, and will increase epi/NE synthesis. This activates Beta-1 Receptors on JG cells, and activates the RAAS

Question 37

What is Bartter's syndrome?

Answer 37

Renal defect of Na reabsorption and aldosterone failure to reabsorb Na and renal resistance to ANG II (acts just like spironolactone? diuretics) Causes JG cell hyperplasia, but still no Na reabsorption

Question 38

Is there HTN or peripheral edema with Bartter's syndrome?

Answer 38

Nah dawg

Question 39

What is Liddle syndrome?

Answer 39

AD defect of Na channels in the kidney, that usually presents with high ECF, low renin