Final Exam (Previous Quiz Questions) Flashcards
The tropic hormone secreted from the ANTERIOR pituitary that stimulates thyroxine (T4) release from the thyroid gland is?
Thyroid-Stimulating Hormone (TSH, thyrotropin)
These types of hormone are easily absorbed through the skin via gel, cream, or patch - what are they?
steroid hormones
Human Growth Hormone (HGH) exerts its effects on cells via what?
Insulin-like Growth Factor (IGF-1)
A 25 year old female presents to your office with her 4 month old son. She reports to you that two months ago after delivering her son, she began noting diminished milk production. Upon further questioning, she also complains of fatigue, diminished libido and abnormally dry skin. Physical exam is remarkable for diminished amount of pubic and axillary hair. What is your most likely DX?
Sheehan's Syndrome common ssx: - Inability to breast-feed (breast milk never "comes in") - Fatigue. - Lack of menstrual bleeding. - Loss of pubic and axillary hair. - Low blood pressure.
A surge in which anterior pituitary hormone triggers ovulation?
Luteinizing hormone (LH) - triggers ovulation, stimulates corpus luteum and secretion of PROGESTERONE*
MALES:
- stimulates Leydig cells to produce testosterone
- released in response to HIGH frequency pulses of GnRH
Severing neuronal connections between the hypothalamus and the pituitary would affect the secretion of which pituitary hormone? Why?
Oxytocin
- secreted from POSTERIOR pituitary which is connected by NEURONS to the hypothalamus
Agents that are secreted by a cell and act only on nearby or neighboring cells are known as what?
Paracrine agents
A 42 y/o while male PTC with complaints of “sugar problems.” He brings a copy of the report that was obtained on his routine insurance screening test. The report shows fasting glucose of 136 mg/dL (normal range: 70-100 mg/dL) and a follow-up fasting glucose level of 142 mg/dL. During a review of systems the patient complains of weight gain, trouble speaking and vision problems over the past several months. He specifically comments that his favorite hat is now too small on him. During examination of the patients cranial nerves - which visual field cut would be expected?
Bitemporal hemianopia (visual field deficit on the lateral visual field BL)
- patients presenting with bitemporal hemianopsia or unexplained visual field deficits or visual loss should be considered to have a pituitary OR hypothalamic disorder until proven otherwise*
This hormone:
- has elevated levels during the evening and early morning hours
- acts as an immunomodulator
- acts on peripheral receptors to maintain body wide circadian rhythms
- and is secreted by the pinealocytes
which hormone is this and what amino acid is it synthesized from?
Melatonin
- synthesized from TRYPTOPHAN
(his quiz says: synthesized from tyrosine - we all know that’s wrong ie - that’s the answer, NOT SYNTHESIZED FROM TYROSINE)
This hormone, does NOT require carrier proteins to be transported in the plasma, which hormone is it?
Insulin
all of the following require transport proteins:
- pregnenolone
- 1,25(OH)2 Vitamin D
- Thyroxine (T4)
- Cortisol
This hormone binds directly to intracellular/intranuclear receptors to exert its action on cell function - which hormone is it?
Thyroxine (T4)
T/F - pituitary microadenomas are often managed medically using dopamine antagonists?
False
- managed with dopamine AGONISTS
Other fun facts:
- pituitary adenomas can be life-threatening
- hypogonadism is a frequent manifestation of pituitary adenomas
- Mass effects from pituitary adenomas may increase intracranial pressure
- achondroplastic dwarfism is NOT the result of an endocrine disorder (it’s genetic)
Dopamine agonists (such as cabergoline) would have what effect on prolactin secretion from the anterior pituitary?
it would DECREASE release of Prolactin
Which condition is most commonly found in obese females with a history of multiple pregnancies and HTN?
Empty Sella Syndrome
common ssx:
Empty sella is often an incidental imaging finding w/out associated symptoms.
If symptoms:
- headaches, symptom of elevated spinal fluid pressure
- symptoms of hypopituitarism
- visual symptoms, can sometimes be due to downward, prolapse of the optic chiasm into the empty sella.
ACTH stimulates release of which hormones from the adrenal cortex?
Cortisol
DHEA-S (androgens)
Which hormone is most commonly hyper-secreted in pituitary adenomas?
Prolactin
What is the most common cause of dwarfism in children?
Achondroplastic Dwarfism
- a spontaneous mutation of the fibroblast growth factor receptor
A 43 y/o F patient presents with a moon face, truncal obesity, HTN, purple striae, buffalo hump, fragile skin and impaired glucose tolerance. In addition, a visual exam reveals bitemporal hemianopsia - what does she most likely have?
Cushing’s disease
A 35 y/o F PTC with thick jaw, prominent brow, large hands, HTN, arthritis, menstrual disturbances and diabetes mellitus. A 5 mm pituitary adenoma was detected on MRI of her head. This adenoma is most likely hyper-secreting which hormone?
Growth Hormone
- ie ACROMEGALY
- occurs after epiphyseal plates are closed, causing thick jaw bones, fingers and toes.
Which of the following DOES NOT increase growth hormone secretion? - low blood glucose - estrogen - cortisol - strenuous exercise - deep sleep ?
Cortisol does not increase the release of GH.
- things that stimulate GH hypoglycemia, fasting glucagon ghrelin estrogen androgens (in puberty) strenuous exercise nicotine vitamin B3 deep sleep
antidiuretic hormone (ADH) is primarily released in response to what?
increased serum OSMOLALITY
osmolality:
the concentration of a solution expressed as the total number of solute particles per kilogram.
The two hormones released from the neurohypophysis are manufactured where?
Paraventricular and Supraoptic Nuclei of the Hypothalamus
These can all be precipitating factors for this condition: - meningitis - pneumonia - pulmonary carcinoma (SCC) - head trauma what is this condition?
Syndrome of Inappropriate Anti-Diuretic Hormone (SIADH)
- characterized by excessive release of ADH (from posterior pituitary or other source)
- increase in blood volume (hypervolemia) often results in dilutional hyponatremia where plasma sodium levels are lowered and total body fluid is increased.
- lithium medications are NOT an etiology
This may result from SIADH, adrenal insufficiency (Addison’s disease), or “beer potamania”
Euvolemic Hyponatremia
if associated with CHF or renal failure - hypervolemic hyponatremia
In pregnancy, this hormone is primarily responsible for uterine contraction at delivery as well as milk ejection from the breast - which hormone is this?
oxytocin
A 66 y/o M with a 50-pack year history of cigarette smoking comes to the clinic complaining of chronic cough, with dyspnea, and blood in his sputum. He says he has been feeling lethargic and has lost 40 lbs over the past 3 months with no changes in diet or exercise. While awaiting an x-ray of the chest, the patient suffers a seizure and is rushed to the emergency department of the nearest hospital. Lab studies show a serum sodium level of 120 mEq/L (N = 135-145 mEq/L) - what is most likely to be elevated in this patient?
ADH (anti-diuretic hormone)
Diabetes insipidus is a disease characterized by the passage of what?
large volumes of dilute urine
In this specific illness, urine concentrates when synthetic ADH is administered - what is it?
Neurogenic (central) diabetes insipidus
- synthetic ADH is given orally or by nasal spray
Too rapid IV infusion of SODIUM can result in what?
Central Pontine Myelinolysis
35 y/o M ptc complaining of increased urinary frequency, polyuria, and an insatiable thirst. He was recently started on a new mediation by his psychiatrist. Labs show the patient is hypernatremic and has decreased urinary osmolarity. Which of the following drugs is most likely contributing to this patients current condition?
- carbamazepine
- lithium
- fluoxetine
- phenobarbital
- clomipramine
Lithium
Dipsogenic diabetes insipidus is caused by a defect or damage to what?
HYPOTHALAMUS
- causes malfunction of the thirst mechanism
In the anterior pituitary, hypothalamic neurons regulate endocrine cells, how??
hypothalamic neurons release peptide hormone into the hypophyseal portal blood system to the anterior pituitary
In a 35y/o F with SIADH, lab findings would typically including all of the following except what?
- serum sodium < 135 (N is 135-145 mEq/L)
- BUN < 10 (N is 7-20mg/dL)
- Serum potassium > 5.0 (N is 3.5-5 mEq/L)
- Uric acid < 4 mg/dL (N is 2.4-6 mg/dL)
- Reduced anion gamp
Serum potassium levels are usually unaffected in SIADH.
- this with hyponatremia might suggest TRUE adrenal fatigue ie Addison disease
True or False
Oxytocin is secreted exclusively by the posterior pituitary gland.
FALSE
oxytocin is secreted by several other tissues such as
- adrenal medulla
- thymus
- pancreas
What is the most metabolically active thyroid hormone?
Triiodothyronine
What is the most common cause of hypothyroidism in the USA?
Autoimmune Thyroiditis
Inhibitors of thyroid hormone secretion, function and metabolism include all of the following EXCEPT:
- estrogen
- growth hormone
- dopamine
- cortisol
- somatostatin
Growth Hormone
thyroid hormone exerts a permissive effect upon the anabolic and metabolic effects of GH and increases pituitary synthesis of GH, GH increases peripheral conversion of T4 to T3.
Tremors, nervousness and increased heart rate can be symptoms of all the following EXCEPT:
- increased activation of the SNS
- excessive secretion of Epi from the Adrenal medulla
- Myxedema coma
- Postpartum thyroiditis
- Thyroid storm
Myxedema coma
Which statement is not true regarding thyroid parafollicular cells?
- secrete a peptide hormone involved in inhibiting bone resorption
- are the cell type found proliferating in medullary thyroid cancers
- contain Na/I symporters
- found in the spaces between thyroid follicles
- none of the above
Parafollicular cells of the thyroid DO NOT contain Na/I symporters, these are ONLY found on thyroid follicular cells to concentrate iodine
A 44 y/o F with a history of pernicious ptc complaining of anxiety and occasional palpitations. She has unexplained weight loss of 10lbs and multiple daily bowel movements. She has not had a menstrual period in four months. She has a thyroid bruit and a 4x3cm oval, NT soft-tissue mass lateral to the thyroid cartilage. What is a possible etiology?
thyroid adenoma
True or False In Grave's disease - TSH levels are elevated, - free T3 and T4 levels are increased and - TPOAb's are elevated.
FALSE
