Exam 3- Endocrine Flashcards
Primary messengers (regarding hormones)
Extracellular signaling
Bind to cell receptor site
Secondary messengers (regarding hormones)
Intracellular signaling
Released after hormone binds to the receptor
Where do hormones go when they aren’t needed anymore
Inactivated by the liver
Excreted by the kidneys
Water soluble hormones characteristics
Circulate in blood
Cannot diffuse into cell
Bind to receptors in cell surface
Message sent inward (primary messenger)
Lipid soluble hormone characteristics
Made from cholesterol
Diffuse across cell membrane
Bind to intracellular receptors (secondary messengers)
Target cells
What the hormones bind to
If they have more receptors—> more sensitive to the hormone
Up regulation
If there is a low concentration of hormones the number of receptors increases
Down regulation
If there is a high concentration of hormones the number of receptors decreases
Positive feedback
When the hormone releases, the physiologic reaction increases
Ex) oxytocin increases labor contractions
Negative feedback
The hormone releases brings the body back to homeostasis (reverses the change)
Ex) high calcium in blood—> stops PTH production
Hypothalamus hormones
Thyrotropin releasing hormone
Corticotropin releasing hormone
Pituitary gland hormones
Growth hormone
Thyroid stimulating hormone
ACTH
Luteinizing hormone
ADH
Pineal gland hormones
Melatonin
Thyroid hormones
Triiodothyronine (T3)
Thyroxine (T4)
Calcitonin
Parathyroid hormones
PTH
Parathyroid hormones
PTH
Adrenal hormones
Medulla- catecholamines
Cortex- steroid hormones
—> mineralocorticoid= aldosterone
—> glucosteroid = cortisol
—> androgen = testosterone
Pancreatic hormones
Glucagon
Insulin
Thyroid gland functions
Metabolism, mood, body temp
Parathyroid gland function
Regulate serum calcium levels
Stimulate kidneys to activate vitamin D for calcium absorption
Adrenal gland function
BP regulation, stress response, sexual development
How does Acromegaly occur
Overproduction of growth hormone
Who is at risk for acromegaly
40 years or more in age
Both men and women
Cause of acromegaly
Benign tumor that stimulates growth hormone
Manifestations of acromegaly
Overgrowth of tissue in hands, feet, face
Hyperglycemia
How to diagnosis acromegaly
Look at insulin like growth factor
Elevated fatty acids
Mechanism of hypopituitarism
Decreased production of pituitary hormones
Etiologies for hypopituitarism
Decreased pituitary hormone, head, injuries, radiation to head and neck, autoimmune disease
Manifestation of hypopituitarism if growth hormone is affected
Lack of ambition
Change in body fat %
Social isolation
Manifestations of hypopituitarism if TSH is affected
Weight gain
dry skin
constipation
cold sensitivity
Manifestations of hypopituitarism ACTH is affected
Hypotension
fainting
frequent/ prolonged infections
Manifestations of hypopituitarism, if Luteinizing hormone is affected
Women: irregular period, loss of pubic hair, ability to produce milk
Men: mood changes, erectile dysfunction, decreased body hair
Mechanism of diabetes insipidus
Low production of ADH
or decreased renal response to ADH
Etiologies of diabetes insipidus
Brain tumor, CNS infection, renal damage
Manifestations of diabetes insipidus
Excessive peeing and thirst
hypernatremia
tachycardia
Mechanism for Syndrome of Inappropriate Antidiuretic Hormone (SIADH)
Excess release of ADH
Risk factors for syndrome of inappropriate antidiuretic hormone
65 years or more
Cancer diagnosis
Etiologies for SIADH
Brain tumor, meningitis, encephalitis drugs (antipsychotics)
Manifestations of SIADH
Low urine output but increased body weight
Fatigue
Hyponatremia
What is a disorder of the pineal gland?
Insomnia
What is a disorder of the pineal gland?
Insomnia
Mechanism of a goiter
Enlarged thyroid due to insufficient thyroid hormone
Etiologies of goiter
The thyroid enlarges to try and capture more iodine for thyroid hormone production
What does goiter put you at risk for?
Hyperthyroidism
Toxic nodular goiter
Risk factors for goiter
Low iodine diet, female, auto immune disease, 40+ yrs
Manifestations of goiter
Large bulging neck
Dysphasia
Dysphagia
SOB
Dysphasia vs dysphagia
Trouble speaking
Trouble swallowing
Mechanism leading to hyperthyroidism
Over active thyroid gland or constant release of thyroid hormoneS
Who is at risk for hypothyroidism
Female
20-40 years old
What is the most common type of hyperthyroidism?
Graves disease
Etiologies of hyperthyroidism
Auto immune disorder, toxic nodular goiter, excess iodine intake
Manifestations of hyperthyroidism
Weight loss
diarrhea
fatigue
restlessness
exopthalmus (eye bulging)
How to diagnose hyperthyroidism
Radioiodine uptake test
Hyp____thyroidism is more common
Hypo
Who is at risk for hypothyroidism
Female, critically ill, 65+ years, iodine deficient
What gland is the problem in primary hypothyroidism?
Thyroid
What gland is the problem and secondary hypothyroidism?
Pituitary
What is Myxedema
An advanced form of hypothyroidism with lots of symptoms
Manifestations of hypothyroidism
Weight gain, constipation, slurred speech, cold intolerance
Who is at risk for thyroid cancer
Female, white or Asian, radiation exposure, goiter history
Manifestations of thyroid cancer
Painless but palpable thyroid nodules
palpable lymph nodes
difficulty swallowing, talking, breathing
How to diagnose thyroid cancer
PET scan to check for metastasis
Mechanism of hyperparathyroidism
Overproduction of PTH
Related to hypercalcemia
Etiologies of hyperparathyroidism
Primary: tumor or enlargement
Secondary: severe calcium deficiency, vitamin D deficiency, CKF
How to diagnose hyperparathyroidism
DEXA scan to check bone density
Manifestations of hyperparathyroidism
Hypercalcemia
hypophosphatemia
muscle weakness
bone pain
Complications of hyperparathyroidism
Osteoporosis, renal failure, kidney stones, fractures
Mechanism for hypoparathyroidism
Inadequate PTH and calcium leads to hypocalcemia
Etiologies for hypoparathyroidism
Iatrogenic procedures, autoimmune, idiopathic
Manifestations of hypoparathyroidism
Tetany, trousseau sign, chvostek sign
Why does Cushing syndrome occur
Chronically high cortisol levels
ACTH secreting mass on pituitary
Inherited
How to diagnose Cushing syndrome
Check pituitary and adrenal for masses
Addison’s Disease mechanism
Decrease in all adrenal steroids
Etiologies of adrenocortical insufficiency
Addison’s disease, adrenal gland infection, cancer
Manifestations of adrenocortical insufficiency
Weight loss
Hypotension
Bronzing of skin
Diagnostic tests for adrenocortical insufficiency
Cortisol levels in the morning
ACTH hormone stimulating test
What does the ACTH stimulating test do
Measures how well adrenal glands respond to ACTH
Steps of a ACTH stimulating test
ACTH and cortisol blood levels are drawn
Synthetic ACTH is administered
After 1hr redraw ACTH and cortisol
Normal ACTH stimulating test results
Cortisol levels should increase
If adrenal glands are the issue on the ACTH stimulating test
Cortisol and aldosterone both low
Cortisol doesn’t increase during test
If hypothalamus or pituitary is problem on ACTH stimulating test
At first hormones will respond normally
Chronic when adrenal glands atrophy/ low cortisol levels
Hyperaldosteronism due to…..
Renal dysfunction from benign adrenal tumor, renal artery stenosis, CKD
Manifestations of hyperaldosteronism
Hypertension
Headaches
Hyoernatremia
Hypokalemia= cardiac dysrhythmia
How to diagnose hyperaldosteronism
Check aldosterone, sodium, and potassium levels
What is pheochromocytoma
A hormone secreting tumor
Leads to excess catecholamine secretion
Etiology of pheochromocytoma
The tumor periodically turns on and off due to trauma tumor, or stress
How to diagnose pheochromocytoma
24 urine collection of:
Metanephrines
Catecholamines
Creatinine
Manifestations of pheochromocytoma
Severe hypertension
Chest/ab pain
Cardiomyopathy
Multi organ failure
What criteria symptoms must be seen for a diagnosis of metabolic syndrome
At least 3:
Hyperglycemia
Hypertension
High triglycerides levels
Abdominal obesity
Low HDLs
3 P’s of Diabetes Manifestations
Polydipsia (increased thirst)
Polyuria (increased urination)
Polyphagia (increased hunger)
