Deck 49: Peptide Hormones

Question 1

You are attending to your 51-year-old female patient who has come to you complaining that she is losing weight, yet is continuously hungry and eating more than usual. She also reports that she is experiencing irritability, insomnia, diarrhea, muscle weakness, heart palpitations, and intolerance to heat. You suspect your patient is suffering from Graves disease. Assay for which of the following in her blood would most likely confirm your diagnosis?

A) decreased growth hormone
B) decreased vasopressin
C) elevated insulin
D) insulin receptor autoantibodies
E) thyroid hormone receptor autoantibodies

Answer 1

thyroid hormone receptor autoantibodies

Question 2

A 67-year-old postmenopausal woman is being examined by her physician due to back pain, an apparent loss of height, and the inability to stand erect. Her physician orders a spinal x-ray which shows vertebral thinning typical of osteoporosis. Which of the following hormones would be the most useful in attempting to treat this patient's condition?

A) ACTH
B) growth hormone
C) parathyroid hormone
D) thyroid hormone
E) vitamin D

Answer 2

parathyroid hormone

Question 3

You are treating a 27-year-old male patient for recent onset of hypertension. The patient reports that he has not consumed any alcohol nor does he use any medications or illegal drugs. Analysis of serum electrolytes indicates a reduced level of potassium. You suspect the patient is experiencing a disruption in the normal responses to vascular volume. A blood test to assay for an increase in which of the following hormones would be useful in the diagnosis of the cause of the hypertension in this patient?

A) atrial natriuretic peptide
B) oxytocin
C) parathyroid hormone
D) renin
E) thyroid-stimulating hormone

Answer 3

renin

Question 4

You are an experimental endocrinologist studying the effects of a peptide analog on the functions of the kidney. When you administer the analog to laboratory mice you are able to measure a significant increase in urinary excretion of sodium. Which of the following known peptides exerts effects most similar to your peptide analog?

A) atrial natriuretic peptide
B) calcitonin
C) irisin
D) oxytocin
E) renin

Question 5

You are treating a 63-year-old postmenopausal woman who has complained that she no longer has the ability to stand erect without pain. She also reports that she suffered a minor ulna fracture when she accidently bumped into the door frame entering her bathroom. An x-ray of her spine demonstrates vertebral thinning typical of osteoporosis. In the absence of recombinant parathyroid therapy, which of the following hormones would be most useful in treating this woman's condition?

A) ACTH
B) calcitonin
C) corticotropin-releasing hormone
D) growth hormone
E) thyroid stimulating hormone

Question 6

A hormone of the hypothalamic-pituitarygonadal axis is known to stimulate follicular development and estrogen synthesis by granulosa cells of the ovary of female. In males, this same hormone promotes testicular growth and it enhances the synthesis and secretion of testosterone and dihydrotestosterone by Sertoli cells. Which of the following is the hormone exerting these actions?

A) follicle-stimulating hormone
B) gonadotropin-releasing hormone
C) growth hormone
D) luteinizing hormone
E) prolactin-releasing hormone

Question 7

You are treating a 37-year-old woman who complains of an extreme thirst. She gets the greatest relief from consuming large quantities of ice water or by sucking on ice cubes. She reports that she also has to frequently urinate. You suspect she may be suffering from diabetes mellitus but assay for urine glucose shows that it is not elevated. Indeed the patient's urine is quite dilute. A deficiency in which of the following hormones is the most likely cause of the symptoms in this woman?

A) ACTH
B) follicle-stimulating hormone
C) renin
D) thyroid-stimulating hormone
E) vasopressin

Question 8

As the level of visceral fat increases, there is a concomitant loss of peripheral tissue responses to insulin. Adipose tissue responses to these metabolic changes include a reduced secretion of which of the following adipokines?

A) adiponectin
B) adipsin
C) IL-6
D) leptin
E) resistin

Question 9

Blocking the actions of which of the following hormones would be expected to lead to the greatest level of appetite suppression?

A) adiponectin
B) ghrelin
C) GLP-1
D) obestatin
E) peptide tyrosine tyrosine, PYY

Question 10

You are treating a patient exhibiting hypotension who also manifests with signs of hepatic failure. The hypotension associated with liver failure most closely reflects an imbalance in which of the following hormone systems?

A) ACTH
B) aldosterone
C) corticotropin-releasing hormone (CRH)
D) cortisol
E) renin-angiotensin

Question 11

Interference with the action of angiotensinconverting enzyme (ACE) is an effective means at reducing elevations in blood pressure. The circulating concentration of which of the following hormones would be affected as a consequence of the use of ACE inhibitors?

A) ACTH
B) aldosterone
C) corticotrophin-releasing hormone, CRH
D) estradiol
E) gonadotropin-releasing hormone, GnRH

Question 12

Which of the following is the hypophyseotropic hormone that regulates the activity of the lactotrophs of the anterior pituitary?

A) corticotrophin-releasing hormone, CRH
B) gonadotropin-releasing hormone, GnRH
C) growth hormone-releasing hormone, GRH
D) prolactin-releasing factor, PRF
E) thyrotropin-releasing hormone, TRH

Question 13

In renal insufficiency, calcium absorption is reduced and leads to increased bone resorption, a condition referred to as renal osteodystrophy. Treatment with which of the following can assist in the amelioration of the symptoms of this condition?

A) antidiuretic hormone
B) calcitonin
C) calcitriol
D) growth hormone
E) parathyroid hormone

Question 14

A 17-year-old adolescent boy who reports to his physician that he is incapable of obtaining an erection is also quite embarrassed by the apparent enlargement of his breasts (gynecomastia). These symptoms, when present in males, are associated with an excessive production of which of the following hormones?

A) corticotropin-releasing hormone
B) gonadotropin-releasing hormone
C) growth hormone
D) melanocyte-stimulating hormone
E) prolactin

Question 15

Acromegaly is characterized by protruding jaw; enlargement of the nose, hands, feet, and skull; and a thickening of the skin. This disorder is the result of excessive production of which of the following hormones?

A) corticotropin-releasing hormone
B) gonadotropin-releasing hormone
C) growth hormone
D) insulin-like growth factor II
E) thyroid-stimulating hormone

Question 16

A patient is diagnosed with problems in emptying the gallbladder. On a blood checkup, one hormone/ peptide that is known to stimulate gallbladder contraction is inappropriately low. Which of the following hormones is most likely deficient leading to the observed symptoms?

A) cholecystokinin
B) gastrin
C) GLP-1
D) pancreatic polypeptide
E) peptide tyrosine tyrosine (PYY)

Question 17

The pancreas play an important role in the control of blood glucose by its secretion of insulin and glucagon. The release of insulin and glucagon is inhibited by somatostatin, which is also secreted by the pancreas. Which of the following cells of the pancreas secrete somatostatin?

A) acinar cells
B) α-cells
C) β-cells
D) δ-cells
E) F cells

Question 18

A well-nourished 21-year-old woman presents with hypocalcemia. Her blood concentration of parathyroid hormone (PTH) is 150 pg/mL (normal 10-65 pg/mL). Her blood concentration of 1,25-dihydroxycholecalciferol is normal. Her BUN is normal. She is treated with a synthetic version of human PTH, and her blood calcium concentration normalizes. Which of the following is most likely causing her hypocalcemia?

A) decrease in total number of PTH receptors in kidney
B) deficiency of 1-α-hydroxylase activity in kidney
C) hepatocellular defect
D) secretion of an inactive PTH hormone molecule
E) severe vitamin D deficiency

Question 19

Which of the following refers to peptide hormones whose actions are exerted on cells adjacent to their site of synthesis but not on the cell of synthesis?

A) autocrine
B) chemokine
C) exocrine
D) paracrine

Question 20

A motor vehicle accident caused complete pituitary stalk transection. Secretion of all pituitary hormones is lost except for one, whose blood level actually increases. Which one of the following pituitary hormones is distinctive in that its primary control is by inhibition rather than stimulation by the hypothalamus?

A) gonadotropin-releasing hormone
B) growth hormone
C) prolactin
D) proopiomelanocortin, POMC
E) thyroid-stimulating hormone

Question 21

A 39-year-old woman reports headaches, weakness and fatigue, and frequent urination over the past several weeks. Physical examination reveals diastolic hypertension. Laboratory findings include hypokalemia and reduced renin levels. Which of the following is the most likely cause of these various findings?

A) Conn syndrome
B) diabetes insipidus
C) diabetes mellitus
D) pheochromocytoma
E) polycystic renal disease

Question 22

A 55-year-old male presents with headache and visual field changes. He is 6½ ft tall and has a puffy face. His skin on hands and feet is thickened, and compared to a picture of him at age 30, his nose, ears and jaw seem larger. His teeth are separated (diastema). He seems to sweat more and complains of bad sleep. Which of the following would provide the greatest therapeutic benefit in this patient?

A) GHRH
B) growth hormone
C) insulin
D) somatostatin
E) thyroid hormones

Question 23

Altered plasma renin levels can occur in both normal and pathologic conditions. Which of the following states is associated with a decrease in plasma renin levels?

A) heart failure
B) primary aldosteronism
C) renal artery stenosis
D) salt restriction
E) upright posture

Question 24

A person has an elevated plasma osmolality and reduced plasma antidiuretic hormone (ADH) level and excretes a large volume of osmotically dilute urine. The urine contains no glucose. What is the most likely explanation for this situation?

A) congestive heart failure
B) nephrogenic diabetes insipidus
C) neurogenic diabetes insipidus
D) primary polydipsia
E) uncontrolled diabetes mellitus

Question 25

Although most cases of hypertension are "essential," meaning the underlying disorder is unknown, about 10% of cases are "secondary hypertension" due to a specific, usually treatable cause. Which of the following conditions can lead to secondary hypertension?

A) adrenal insufficiency
B) estrogen deficiency
C) hyperparathyroidism
D) renal artery stenosis
E) volume depletion

Question 26

Renin is released from the kidneys in response to a drop in blood pressure. The function of renin is to generate angiotensin I, which is accomplishes by which of the following mechanisms?

A) interaction with a steroid receptor in the cell nucleus
B) proteolysis of antidiuretic hormone (ADH, vasopressin)
C) proteolytic cleavage of the precursor in blood
D) stabilization of angiotensin I mRNA
E) transcriptional activation of the angiotensin I gene

Question 27

Parathyroid hormone regulates the concentration of the most potent vitamin D metabolite by increasing which of the following conversion?

A) cholecalciferol to 24,25-dihydroxycholecalciferol
B) cholecalciferol to 25-hydroxycholecalciferol
C) 7-dehydrocholesterol to cholecalciferol
D) ergosterol to ergocalciferol
E) 25-hydroxycholecalciferol to 1,25-dihydroxycholecalciferol

Question 28

You are treating a 54-year-old man with extreme abdominal pain. Ultrasonic examination shows enlargement of the pancreas with lobular structures clearly visible. Biopsy of the tissue indicates the patient has a glucagonoma. Which of the following laboratory findings would also be expected in this patient?

A) decreased (<6%) hemoglobin A1c
B) decreased serum concentration of free fatty acids
C) hypoinsulinemia
D) increased (350-400 mg/dL) serum glucose concentration
E) increased serum concentration of amylin

Question 29

Administration of which of the following hormones is most likely to produce a positive nitrogen balance?

A) aldosterone
B) cortisol
C) epinephrine
D) glucagon
E) insulin

Question 30

You are studying the effects of atrial natriuretic factor (ANF) in an experimental animal model. You find that addition of ANP to these animals results in increased activity of a guanylate cyclase. Which of the following is most likely to result from the increased cGMP concentrations in this animal?

A) activation of protein kinase activity
B) hydrolysis of GTP in the GTP-G protein complex
C) increased formation of phosphorylated protein kinase A
D) increased intracellular cAMP concentrations
E) stabilization of the ANF receptor