Endocrine Flashcards by Denise Nelson

What is the adrenal cortex derived from?

Mesoderm

How well did you know this?

Not at all

Perfectly

What is the adrenal medulla derived from?

Neural crest cells

How well did you know this?

Not at all

Perfectly

What is the zona glomerulosa regulated by and what does it produce?

AT II

Mineralocorticoids (aldosterone)

How well did you know this?

Not at all

Perfectly

What is the zona Fasciculata regulated by and what does it produce?

ACTH, CRH

Glucocoriticoids (cortisol)

How well did you know this?

Not at all

Perfectly

What is the zona Reticularis regulated by and what does it produce?

ACTH, CRH

Androgens (DHEA)

How well did you know this?

Not at all

Perfectly

What are the cells of the adrenal medulla?

Chromaffin cells

How well did you know this?

Not at all

Perfectly

What is the adrenal medulla regulated by and what does it produce?

Preganglionic SNS

Catecholamines (epi/norepi)

How well did you know this?

Not at all

Perfectly

What are the insulin dependent transporters and in what tissues would you find them?

GLUT4: adipose tissue, striated muscle

How well did you know this?

Not at all

Perfectly

What are the insulin independent transporters and in what tissues would you find them?

GLUT1: RBCs, brain, cornea, placenta
GLUT2 (bidirectional): β islet cells, liver, kidney, small intestine
GLUT3: brain, placenta
GLUT5 (fructose): spermatocytes, GI tract

How well did you know this?

Not at all

Perfectly

What tonically inhibits prolactin?

Dopamine from the hypothalamus

How well did you know this?

Not at all

Perfectly

Function of Ghrelin

Stimulates hunger (orexigenic effect) and GH release (via GH secretagog receptor)
Produced by stomach

How well did you know this?

Not at all

Perfectly

Function of Leptin

Satiety hormone. Produced by adipose tissue.

How well did you know this?

Not at all

Perfectly

Function of endocannabinoids

Act at cannabinoid receptors in hypothalamus and nucleus accumbens, two key brain areas for the homeostatic and hedonic control of food intake: ↑ appetite

How well did you know this?

Not at all

Perfectly

ADH

Synthesized in hypothalamus; released by post pit

Regulates serum osmolarity (V2-r)and BP (V1-r)

How well did you know this?

Not at all

Perfectly

17 alpha hydroxylase def leads to what?

Incr: mineralocorticoids (aldosterone), BP
Decr: cortisol, sex hormones, [K]

How well did you know this?

Not at all

Perfectly

21-hydroxylase def leads to what?

Incr: sex hormones, [K], renin
Decr: aldosterone, cortisol, BP

How well did you know this?

Not at all

Perfectly

Mechanism of Ca homeostasis

↑ in pH -> ↑ in affinity of albumin for Ca -> hypocalcemia

How well did you know this?

Not at all

Perfectly

Function of vitamin D

↑ absorption of dietary Ca2+ and PO43−

Enhances bone mineralization

How well did you know this?

Not at all

Perfectly

Function of PTH

↑ bone resorption of Ca2+ and PO43−
↑ kidney reabsorption of Ca2+ in DCT
↓ reabsorption of PO43− in PCT
↑ calcitriol production by stimulating kidney 1α hydroxylase in proximal convoluted tubule

How well did you know this?

Not at all

Perfectly

Source of PTH

Chief cells of parathyroid

How well did you know this?

Not at all

Perfectly

Source of calcitonin

Parafollicular cells (C cells) of thyroid

How well did you know this?

Not at all

Perfectly

Function of calcitonin

↓ bone respiration of Ca (tones done serum Ca)

How well did you know this?

Not at all

Perfectly

Endocrine hormones that signal via cAMP

FSH, LH, ACTH, TSH, CRH, hCG, ADH (V2-receptor), MSH, PTH, calcitonin, GHRH, glucagon, histamine (H2-receptor)
(FLAT ChAMP)

How well did you know this?

Not at all

Perfectly

Endocrine hormones that signal via cGMP

BNP, ANP, EDRF (NO)

BAD GraMP

Endocrine hormones that signal via IP3

GnRH, Oxytocin, ADH (V1-receptor), TRH, Histamine (H1-receptor), Angiotensin II, Gastrin (GOAT HAG)

Endocrine hormones that signal via intracellular receptors

Progesterone, Estrogen, Testosterone, Cortisol, Aldosterone, T3/T4, Vitamin D

Endocrine hormones that signal via Receptor tyrosine kinase

(MAP kinase) | Insulin, IGF-1, FGF, PDGF, EGF

Endocrine hormones that signal via Nonreceptor tyrosine kinase

(Jak/STAT) | Prolactin, Immunomodulators (eg, cytokines IL-2, IL-6, IFN), GH, G-CSF, Erythropoietin, Thrombopoietin

Oxidation, organification and coupling in T3/T4 synthesis is carried out by?

Thyroid peroxidase

Thyroid peroxidase is blocked by?

PTU, methimazole

What does PTU block?

Thyroid peroxidase and 5-deiodinase

Etiology of Cushing Syndrome

Incr cortisol: exogenous, adrenal ca, ACTH adenoma (called Cushing disease) or paraneoplastic ACTH secretion

Cushing presentation

Moon facies, HTN, central adiposity, striae, osteoporosis, hyperglycemia, amenorrhea, immunosuppression

How do you diagnose Cushing?

25 hour cortisol and midnight salivary cortisol

High dose dexamethasone test

For Cushing Suppresses cortisol: Cushing disease No suppression: Ectopic ACTH secretion

What is adrenal insufficiency?

Inability of adrenal gland to make enough gluco and mineralo corticoids

Sx of adrenal insufficiency?

weakness, fatigue, orthostatic hypotension, muscle aches, weight loss, GI disturbances, sugar and/ or salt cravings

What is the metyrapone stimulation test for?

Diagnose adrenal insufficiency (metyrapone blocks last step of cortisol synthesis) In 1°: ACTH is elevated, 11-deoxycortisol is low In 2°/3°: both ACTH and 11-deoxycortisol remain low

Cause of primary adrenal insufficiency?

De ciency of aldosterone and cortisol production due to loss of gland function

Sx of primary adrenal insufficiency?

hypotension (hyponatremic volume contraction), hyperkalemia, metabolic acidosis, skin and mucosal hyperpigmentation

What is Addison dz?

Chronic primary adrenal insufficiency

Cause of hyperaldosteronism?

Increased secretion of aldosterone from adrenal gland

Conn syndrome

Primary hyperaldosteronism d/t adrenal adenoma or b/l adrenal hyperplasia

What is the most common adrenal medulla tumor in children?

Neuroblastoma

Presentation of neuroblastoma?

Abdominal distension and a firm, irregular mass that can cross the midline; can also present with opsoclonus-myoclonus syndrome Increased HVA, VMA; homer-wright rosettes, bombesin and NSE positive APUD tumor

What is the most common adrenal medulla tumor in adults?

Pheochromocytoma

Sx of Pheochromocytoma?

secrete epic, norepinephrine and 5-HT: episodic hypertension (Pressure, Pain (HA), Perspiration, Palpitations (tachyP), Pallor)

Presentation of congenital hypothyroid?

Pot-bellied, Pale, Puffy-faced child with Protruding umbilicus, Protuberant tongue, and Poor brain development

Presentation of Subacute granulomatous thyroiditis (de Quervain)

↑ ESR, jaw pain, very tender thyroid

Jod-Basedow phenomenon

Thyrotoxicosis if a patient with iodine deficiency and partially autonomous thyroid tissue is made iodine replete

Nelson syndrome

Enlargement of existing ACTH-secreting pituitary adenoma after bilateral adrenalectomy for refractory Cushing disease Presents with hyperpigmentation, headaches and bitemporal hemianopia

MEN 1

Pituitary tumors, Pancreatic endocrine tumors, Parathyroid adenomas

MEN 2A

Parathyroid hyperplasia, Medullary thyroid carcinoma, Pheochromocytoma

MEN 2B

Medullary thyroid carcinoma Pheochromocytoma | Mucosal neuromas

Rx for SIADH?

``` ADH antagonists (conivaptan, tolvaptan): Block action of ADH at V2-receptor Demeclocycline: ADH antagonist ```

Fludrocortisone

Synthetic analog of aldosterone with little glucocorticoid effects; replace mineralocorticoids in 1° adrenal insuficiency

Cinacalcet

Sensitizes Ca2+-sensing receptor (CaSR) in parathyroid gland to circulating Ca2+: ↓ PTH

SE of antithyroid drugs (thionamides)

Agranulocytos Methimazol: cholestasis Propylthiouracil: hepatic failure