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Flashcards in Endocrine Deck (66)
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1
Q

Which adrenal gland goes to the renal vein before the IVC?

A

Left adrenal gland (same as gonadal vein)

2
Q

Which anterior pituitary hormones are basophils?

A

B-FLAT

Basophils - FSH, LH, ACTH, TSH

3
Q

What type of receptors are insulin receptors?

A

Tyrosine kinase receptors

4
Q
How does insulin affect the following?
Na+:
TGs:
K+:
Amino acids:
A

Sodium retention increased in the kidneys
Triglyceride synthesis increased
Cellular uptake of potassium and amino acids increased

5
Q

Which GLUT receptor is in the brain?

A

GLUT-1: RBCs, brain, cornea

6
Q

What aside from glucose increases insulin release?

A

β2-agonists and Growth Hormone (increases insulin resistance)

7
Q

How does prolactin influence GnRH?

A

Decreases GnRH release

8
Q

How does TRH affect prolactin?

A

TRH increases prolactin

9
Q

What enzymes are used to produce aldosterone from cholesterol?

A
  1. Cholesterol desmolase
  2. 3β-hydroxysteroid dehydrogenase
  3. 21-hydroxylase
  4. 11β-hydroxylase
  5. Aldosterone synthase
10
Q

What enzyme is necessary to produce cortisol and sex hormones? What happens when this enzyme is deficient (For XX and XY individuals)?

A

17α-hydroxylase
XX: lack secondary sexual development
XY: pseudohermaphroditism (ambiguous genitalia and undescended testes)

11
Q

What are the functions of cortisol? (BIG FIB)

A

Blood pressure increase (upregulates α1 receptors on arterioles)
Insulin resistance (diabetogenic)
Gluconeogenesis, lipolysis and proteolysis are increased
Fibroblast activity is DECREASED
Inflammatory and immune responses are DECREASED
Bone formation (osteoblast activity) is DECREASED

12
Q

RANK-L (production induced by PTH) binds RANK on _______ leading to _______ stimulation

A

RANK-L (production induced by PTH) binds RANK on OSTEOBLASTS leading to OSTEOCLAST stimulation

13
Q

How does Magnesium affect PTH secretion?

A

Low serum magnesium causes increased PTH secretion

Very low serum magnesium causes decreased PTH secretion

14
Q

Which endocrine hormones work via a cAMP pathway?

A

FLAT CHAMP

FSH, LH, ACTH, TSH, CRH, hCG, ADH (V2), MSH, PTH

15
Q

Which endocrine hormones work via an IP3 pathway?

A

GOAT HAG

GnRH, Oxytocin, ADH (V1 receptor), TRH, Histamine, Angiotensin II, Gastrin

16
Q

Which endocrine hormones use an intrinsic tyrosine kinase receptor? (MAP kinase pathway)

A

Insulin, IGF-1, FGF, PDGF, EGF

17
Q

What are the functions of T3? (4 Bs)

A

Bone growth
Brain maturation
Beta adrenergic effects (increase CO, HR, SV, contractility)
Basal metabolic rate increase (via increased Na+/K+ ATPase)

18
Q

What is the Wolff-Chaikoff effect?

A

Excess iodine temporarily inhibits thyroid peroxidase causing decreased iodine organification and decreased T3/T4 production

19
Q

What enzyme converts T3 to T4 in the periphery?

A

5’-deiodinase

20
Q

From what cells is a neuroblastoma/pheochromoblastoma derived?

A

Neuroblastoma: Neural crest cells
Pheochromocytoma: Chromaffin cells (derived from neural crest cells)

21
Q

What gene is overexpressed in a neuroblastoma? What is seen in the urine? What is seen on histology?

A

N-myc oncogene is overexpressed
Homovanillic acid (a breakdown product of dopamine) is increased in urine
Homer-wright rosettes seen on histology

22
Q

What is the rule of 10s for pheochromocytoma?

A
10% malignant
10% bilateral
10% extra-adrenal
10% calcify
10% kids
23
Q

What is seen in the urine in a pheochromocytoma?

A

VMA - Vanillymandelic acid (breakdown product of NE and Epi)

24
Q

How does hyperthyroidism affect cholesterol and through what mechanism?

A

Causes hypocholesterolemia due to increased LDL receptor expression

25
Q

Which HLA is associated with Hashimoto’s thyroiditis?

What disease are patients at increased risk for with Hashimoto’s thyroiditis?

A

HLA-DR5; non-Hodgkin lymphoma

26
Q

What are the “6 Ps” of congenital hypothyroidism (cretinism)?

A
Pot-bellied
Pale
Puffy-faced child
Protruding umbilicus
Protuberant tongue
Poor brain development
27
Q

What type of thyroiditis occurs when the thyroid is replaced by fibrous tissue (manifestation of IgG4-related systemic disease)?

A

Riedel thyroiditis

28
Q

De Quervaine thyroiditis is (painful/painless)

Riedel thyroiditis is (painful/painless)

A

De Quervaine thyroiditis is PAINFUL

Riedel thyroiditis is PAINLESS

29
Q

What is a toxic multinodular goiter? What is the Jod Basedow phenomenon for toxic multinodular goiters?

A

Hyperfunctioning follicular cells working independently of TSH due to mutation in TSH receptor
JB: Thyrotoxicosis if a patient with iodine deficiency goiter is made iodine replete

30
Q

How is a thyroid storm treated (3 Ps)

A

Propranolol (β-blockers) , Propylthiouracil, Prednisolone (corticosteroids)

31
Q

What artery is at risk of transection in a thyroidectomy?

A

Inferior thyroid artery

32
Q

Which thyroid cancer is associated with psammoma bodies, orphan annie eye nuclei, and RET and BRAF mutations?

A

Papillary carcinoma (excellent prognosis)

33
Q

Which thyroid cancer is associated with MEN2A and 2B mutations, produces calcitonin, and displays sheets of cells in an amyloid stroma?

A

Medullary carcinoma

34
Q

What is osteitis fibrosa cystica caused by? What are the symptoms of this disease?

A

Primary hyperparathyroidism
Stones (renal), Bones (bone pain), Groans (Weakness and constipation - acute pancreatitis), and psychiatric overtones (depression)

35
Q

What are Chvostek sign and Trousseau sign in hypoparathyroidism?

A

Chvostek sign: Tapping of facial nerve causes contraction of facial muscles
Trousseau sign: Occlusion of brachial artery with BP cuff causes carpal spasm

36
Q

What is pseudohypoparathyroidism and what is a unique finding?

A

Autosomal dominant unresponsiveness of kidney to PTH

Shortened 4th and 5th digits

37
Q

What is the most common cause of death in children with gigantism?

A

Cardiac failure

38
Q

What 2 tests is used to diagnose acromegaly?

A

Failure to suppress serum GH following oral glucose tolerance test and Increased serum IGF-1 levels

39
Q

How does the body maintain near normal volume status in SIADH?

A

Body responds to water retention with decreased aldosterone (leads to hyponatremia)

40
Q

What is the purpose of the HbA1c test in diabetes mellitus?

A

Reflects average blood glucose over prior 3 months

41
Q

Which type of diabetes has a stronger genetic predisposition?

A

Diabetes Type 2 (90% concordance in identical twins)

42
Q

What happens to potassium during diabetic ketoacidosis?

A

Hyperkalemia, but depleted intracellular K+ due to transcellular shift from decreased insulin

43
Q

What is the Whipple triad (associated with insulinoma CNS effects)?

A

Lethargy, syncope, diplopia

44
Q

What diseases are associated with MEN1

A

Pituitary, Parathyroid, and Pancreatic tumors

45
Q

What diseases are associated with MEN2A?

A

Parathyroids
Pheochromocytoma
Medullary Thyroid carcinoma

46
Q

What diseases are associated with MEN2B?

A

Medullary thyroid carcinoma
Pheochromocytoma
Oral/Intestinal ganglioneuromatosis

47
Q

What are the functions of amylin analogs (Pramlintide)?

A

Decreased gastric emptying

Decreased glucagon

48
Q

What are the functions of GLP-1 analogs (Exenatide, Liraglutide)?

A

Increase insulin

Decrease glucagon release

49
Q

What are the functions of DDP-4 Inhibitors (Linagliptin, Saxagliptin, Sitagliptan)?

A

Increase insulin
Decrease glucagon release
*Block the degradation of GLP-1 analogs

50
Q

What is the adrenal cortex derived from?

What is the medulla derived from?

A

Cortex: Mesoderm
Medulla: Neural crest

51
Q

What drugs can cause nephrogenic diabetes insipidus?

What drug can cause SIADH?

A

NDI: Lithium and Demeclocycline (treatment for SIADH)
SIADH: Cyclophosphamide

52
Q

By what mechanism does hyperthyroidism increase basal metabolic rate? Sympathetic nervous system activity?

A

BMR: Increased synthesis of Na+/K+ ATPase

SNS activity: Increased expression of Beta1 adrenergic receptors

53
Q

What transports oxytocin and vasopressin from the hypothalamus to the posterior pituitary?

A

neurophysins

54
Q

Where are β cells located in the pancreas? α cells? What does each produce?

A

β cells (insulin producing) are central and α cells (glucagon) are peripheral

55
Q

CRH increases what three hormones?

A

ACTH, MSH, and β-endorphins

56
Q

What increases somatomedin? What does somatomedin cause?

A

Growth hormone (somatotropin) increases somatomedin which increases somatostatin which suppresses growth hormone release

57
Q

How does cortisol affect IL-2 and histamine release?

A

Blocks IL-2 production (can lead to reactivation of candidiasis and TB) and blocks histamine release from mast cells

58
Q

Which endogenous hormone increases production of macrophage colony-stimulating factor?

A

PTH

59
Q

How does pH affect calcium levels?

A

Increase in pH → increased affinity of albumin (negative charge) to bind calcium → clinical manifestations of hypocalcemia (cramps, pain, paresthesias)

60
Q

Which endocrine hormones use a receptor associated tyrosine kinase (JAK/STAT)? (PIG)

A

Prolactin, Immunomodulators (cytokines and interleukins), Growth hormone

61
Q

Why are sodium levels normal in primary hyperaldosteronism (Conn syndrome or adrenal hyperplasia)?

A

Aldosterone escape: Secretion of ANP to prevent hypernatremia

62
Q

How is primary adrenal insufficiency distinguished from secondary adrenal insufficiency?

A

secondary adrenal insufficiency has no skin/mucosal hyperpigmentation and no hyperkalemia

63
Q

Where can a neuroblastoma occur and how is it differentiated from Wilms tumor?

A

Neuroblastomas can occur anywhere along the sympathetic chain
Presents as a firm, irregular mass that can cross the midline vs. Wilms tumor which is smooth and unilateral

64
Q

Increased cAMP in urine is most likely due to…

A

Primary hyper-parathyroidism (PTH works through Gs pathway)

65
Q

What is pegvisomant?

A

Growth hormone receptor antagonist

66
Q

How does T2DM lead to nephrotic syndrome? Blindness?

A

Nephrotic syndrome: NEG → hyaline arteriorsclerosis → preferential involvement of efferent arterials → glomerular hyperfiltration → microalbuminuria → nephrotic syndrome

Blindness: Glucose freely enters schwann cells → aldose converts glucose to sorbitol → osmotic damage → neuropathy → blindness