Home Books Katzung & Trevor's Pharmacology: Examination & Board Review, 12e

Chapter 37: Hypothalamic & Pituitary Hormones

A young couple (25-year-old male, 23-year-old female) wants to start a family. They have not conceived after 1 year of unprotected intercourse. Infertility evaluation revealed no abnormalities in the female partner and low sperm count in the male. Which of the following is a drug that is purified from the urine of postmenopausal women and is used to promote spermatogenesis in infertile men?

(A) Desmopressin

(B) Gonadorelin

(C) Goserelin

(D) Somatropin

(E) Urofollitropin

Spermatogenesis in males requires the action of FSH and LH. Urofollitropin, which is purified from the urine of postmenopausal women, is used clinically to provide FSH activity. The answer is E.

A 29-year-old woman in her 41st week of gestation had been in labor for 12 h. Although her uterine contractions had been strong and regular initially, they had diminished in force during the past hour. Which of the following agents would be used to facilitate this woman’s labor and delivery?

(A) Dopamine

(B) Leuprolide

(C) Oxytocin

(D) Prolactin

(E) Vasopressin

Oxytocin is an effective stimulant of uterine contraction that is routinely used to augment labor. The answer is C.

A 3-year-old boy with failure to thrive and metabolic disturbances was found to have an inactivating mutation in the gene that encodes the growth hormone receptor. Which of the following drugs is most likely to improve his metabolic function and promote his growth?

(A) Atosiban

(B) Bromocriptine

(C) Mecasermin

(D) Octreotide

(E) Somatropin

This child’s condition is due to the inability of GH to stimulate the production of insulin-like growth factors, the ultimate mediators of GH effects. Mecasermin, a combination of recombinant IGF-1 and the binding protein that protects IGF-1 from immediate destruction, will help correct the IGF deficiency. Because of the inactive GH receptors, somatropin will not be effective. The answer is C.

An important difference between leuprolide and ganirelix is that ganirelix

(A) Can be administered as an oral formulation

(B) Can be used alone to restore fertility to hypogonadal men and women

(C) Immediately reduces gonadotropin secretion

(D) Initially stimulates pituitary production of LH and FSH

(E) Must be administered in a pulsatile fashion

Leuprolide is an agonist of GnRH receptors, whereas ganirelix is an antagonist. Although both drugs can be used to inhibit gonadotropin release, ganirelix does so immediately, whereas leuprolide does so only after about 1 week of sustained activity. The answer is C.

A 27-year-old woman with amenorrhea, infertility, and galactorrhea was treated with a drug that successfully restored ovulation and menstruation. Before being given the drug, the woman was carefully questioned about previous mental health problems, which she did not have. She was advised to take the drug orally. Which of the following is most likely to be the drug that was used to treat this patient?

(A) Bromocriptine

(B) Desmopressin

(C) Human gonadotropin hormone

(D) Leuprolide

(E) Octreotide

Bromocriptine, a dopamine receptor agonist, is used to treat the amenorrhea-galactorrhea syndrome, which is a consequence of hyperprolactinemia. Because of its central dopaminergic effects, the drug should not be used in patients with a history of schizophrenia or other forms of psychotic illness. The answer is A.

A 3-year-old girl was referred to the genetic counselor by her pediatrician. She presents with short stature (height is 85 cm, –3 standard deviations) and appears to have loose skin on her neck. Cytogenetic testing reveals an XO karyotype. Which of the following drugs will allow her to achieve a higher adult height?

(A) Adrenocorticotropin (ACTH)

(B) Corticotropin-releasing hormone (CRH)

(C) Growth hormone-releasing hormone (GHRH)

(D) Gonadotropin-releasing hormone (GnRH)

(E) Somatropin

Adrenocorticotropin (ACTH) is used diagnostically in suspected adrenal insufficiency. Corticotropin-releasing hormone (CRH) is used to distinguish Cushing’s syndrome from ectopic ACTH secretion. GHRH is rarely used as treatment. Its main use is as a diagnostic tool. GnRH can be used to treat infertility. Somatropin, recombinant human GH, promotes growth in children with Turner syndrome (an XO genetic genotype) or chronic renal failure. It also helps combat the AIDS-associated wasting syndrome. The answer is E.

A 3-year-old girl presented with hirsutism, breast enlargement, and a height and bone age that was consistent with an age of 9. Diagnostic testing revealed precocious puberty. Which of the following is the most appropriate drug for treatment of this patient’s precocious puberty?

(A) Atosiban

(B) Follitropin

(C) Leuprolide

(D) Octreotide

(E) Pegvisomant

In precocious puberty, the hypothalamic-pituitary-gonadal axis becomes prematurely active for reasons that are not understood. Treatment involves suppressing gonadotropin secretion with continuous administration of a long-acting GnRH agonist such as leuprolide. The answer is C.

A 47-year-old man exhibited signs and symptoms of acromegaly. Radiologic studies indicated the presence of a large pituitary tumor. Surgical treatment of the tumor was only partially effective in controlling his disease. At this point, which of the following drugs is most likely to be used as pharmacologic therapy?

(A) Cosyntropin

(B) Desmopressin

(C) Leuprolide

(D) Octreotide

(E) Somatropin

Octreotide, a somatostatin analog, has some efficacy in reducing the excess GH production that causes acromegaly. The answer is D.

A 37-year-old woman with infertility due to obstructed fallopian tubes was undergoing ovulation induction in preparation for in vitro fertilization. After 10 d of treatment with leuprolide, the next step in the procedure is most likely to involve 10–14 d of treatment with which of the following?

(A) Bromocriptine

(B) Follitropin

(C) Gonadorelin

(D) hCG

(E) Pergolide

Once the patient’s endogenous gonadotropin production has been inhibited through continuous administration of the GnRH agonist leuprolide, the next step in ovulation induction is the administration of a drug with FSH activity to stimulate follicle maturation. Follitropin is recombinant FSH. The only other drug listed that is used in ovulation induction is hCG, but this is an LH analog. The answer is B.

A 7-year-old boy underwent successful chemotherapy and cranial radiation for treatment of acute lymphocytic leukemia. One month after the completion of therapy, the patient presented with excessive thirst and urination plus hypernatremia. Laboratory testing revealed pituitary diabetes insipidus. To correct these problems, this patient is likely to be treated with which of the following?

(A) Corticotropin

(B) Desmopressin

(C) hCG

(D) Menotropins

(E) Thyrotropin

Pituitary diabetes insipidus results from deficiency in vasopressin. It is treated with desmopressin, a peptide agonist of vasopressin V₂ receptors. The answer is B.

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.

Chapter 37: Hypothalamic & Pituitary Hormones

Send Email

Citation

Jump to a Section

Chapter 37: Hypothalamic & Pituitary Hormones

Pop-up div Successfully Displayed