Deck 40: Disorders of the Pituitary

Question 1

The most common assay used to assess serum concentration of adenohypophyseal hormones is:

A) chromatography.
B) immunoassay.
C) electrophoresis.
D) spectrometry.

Answer 1

immunoassay.

Question 2

The hypothalamic hormone that inhibits prolactin is referred to as prolactin-inhibiting hormone but is actually:

A) thyrotropin.
B) dopamine.
C) adrenaline.
D) interleukin 1.

Answer 2

dopamine.

Question 3

Which one of the following hormones is responsible for normal development of cartilage and bone,mobilizing fat stores,and stimulation of protein synthesis?

A) ADH
B) ACTH
C) GH
D) Prolactin

Answer 3

GH

Question 4

Which one of the following statements concerning hormonal regulation via the feedback loop is correct?

A) The feedback loop is composed of two endocrine organs,the hypothalamus and the pituitary gland.
B) Negative feedback occurs when a structure secretes a hormone in response to a stimulating hormone released from the pituitary.The initial hormone then induces more hormones to be released from the pituitary gland.
C) When a stimulating hormone induces production of a hormone,elevated levels of that hormone shut off further release of the stimulating hormone.This is referred to as negative feedback.
D) In the case of a pituitary adenoma that increases TSH levels,for example,thereby increasing thyroid release of T₄ and T₃,the increased thyroid hormones can easily shut off the release of TSH.

Question 5

Oxytocin is:

A) synthesized by the somatotropic cells of the adenohypophysis and is stored within intracellular granules.
B) released upon stimulation of cell bodies in the hypothalamic paraventricular nucleus.
C) found in the pituitary gland but is mostly localized in the catecholamine-synthesizing cells of the adrenal medulla.
D) the principal hormone that controls the initiation and maintenance of lactation.

Question 6

The most common hypothalamic-pituitary disorder in clinical endocrinology is:

A) hyperprolactinemia.
B) hyperthyroidism.
C) Cushing disease.
D) infertility.

Question 7

The insulin tolerance test is used to assess which one of the following hormones?

A) Growth hormone
B) Thyrotropin
C) Adrenocorticotropic hormone
D) Prolactin

Question 8

The release of thyrotropin-releasing hormone from the hypothalamus stimulates thyrotropin release from the pituitary,which further leads to synthesis and secretion of thyroid hormone from the thyroid gland.When the concentration of thyroid hormone in the blood turns off the release of thyrotropin from the pituitary,this is referred to as what type of feedback?

A) Open loop feedback
B) Negative feedback
C) Positive feedback
D) Inhibitory feedback

Question 9

Which one of the following is not a function of thyrotropin?

A) Action as a carrier protein of circulating thyroid hormones
B) Induction of iodine uptake by the thyroid gland
C) Stimulation of the growth of thyroid follicular cells
D) Stimulation of the release of thyroid hormones from thyroglobulin

Question 10

A 35-year-old man visits his physician with complaints of sudden onset of fatigue,polydipsia,and polyuria.Laboratory results indicate a normal fasting blood sugar.Serum sodium was slightly elevated.The most likely cause of these symptoms and laboratory results would be:

A) diabetes mellitus due to insulin deficiency.
B) secondary hypothyroidism.
C) pituitary adenoma.
D) diabetes insipidus due to hypothalamic dysfunction.

Question 11

Inhibition of growth hormone (GH)occurs through the action of:

A) acetylcholine.
B) somatostatin release-inhibiting hormone.
C) norepinephrine.
D) gonadotropin-releasing inhibiting hormone.

Question 12

Which one of the following statements regarding FSH/LH is incorrect?

A) FSH,secreted by the anterior pituitary,induces growth of the ovum in the follicle of the ovary.
B) LH triggers release of the ovum from the ovarian follicle and produces an initial decrease in estrogen.
C) Progesterone produced by the ruptured follicle (the corpus luteum)causes LH levels to increase.
D) In the male,FSH increases the number of LH receptors on Leydig cells.

Question 13

An example of a hypothalamic hormone would be:

A) growth hormone (GH).
B) thyroid-stimulating hormone (TSH).
C) antidiuretic hormone (ADH).
D) adrenocorticotropic hormone (ACTH).

Question 14

Use of the cosyntropin stimulation test:

A) determines whether the hypothalamic-pituitary-thyroid axis is intact and functional.
B) involves measurement of serum gonadotropins and sex steroid hormones.
C) is indicated when a morning cortisol result is low in addition to indications of adrenal insufficiency.
D) assesses adequacy of GH secretion.

Question 15

The anterior portion of the pituitary gland synthesizes many protein hormones.Another name for this part of the pituitary gland is the:

A) hypothalamus.
B) neurohypophysis.
C) hypophysis.
D) adenohypophysis.

Question 16

A 28-year-old man and his wife visit a fertility clinic.His sperm count is low,but his wife's tests (LH/FSH,estrogen,etc.)all fall within the healthy reference intervals.His history indicates that he had a motor vehicle accident one year previously and was suffering from visual problems.What might be the cause of his oligospermia?

A) Decreased prolactin (PRL)
B) Elevated FSH
C) Decreased LH
D) Elevated GH

Question 17

The follicle-stimulating hormone (FSH)and luteinizing hormone (LH)are important in the reproductive function of the male and female and are released in response to:

A) gonadotropin-releasing hormone (GnRH).
B) corticotrophin-releasing hormone (CRH).
C) TSH.
D) oxytocin.

Question 18

A 45-year-old female complains of fatigue,heat intolerance,and hair loss.Serum thyroxine is abnormally low.What test would confirm that this might be a pituitary disorder?

A) Free T₃
B) Thyroid binding globulin (TBG)
C) Thyroid hormone binding ratio (THBR)
D) Thyrotropin

Question 19

An individual using antidepressants visited her physician with a complaint of water retention.Laboratory results indicated decreased urine volume,low serum sodium,low plasma osmolality,decreased serum uric acid,and urea.Antidiuretic hormone was measured and found to be elevated.What is the likely diagnosis?

A) Acromegaly
B) Hypothyroidism
C) Diabetes insipidus
D) Syndrome of inappropriate ADH secretion (SIADH)

Question 20

Which one of the following hormones is classified as a glycoprotein?

A) Growth hormone
B) Adrenocorticotropic hormone
C) Prolactin
D) Follicle-stimulating hormone