Clinical Chemistry (Endocrinology)

Secretion of hormones by the anterior pituitary may be controlled by the circulating levels of hormones from the respective target gland, as well as hormones secreted by what organ? A. Posterior lobe of the pituitary gland B. Intermediate lobe of the pituitary gland C. Hypothalamus D. Adrenal medulla

An elevated level of which of the following hormones will inhibit pituitary secretion of adrenocorticotropic hormone (ACTH)? A. Aldosterone B. Cortisol C. 17 B-Estradiol D. Progesterone

Which of the following is the major mineralocorticoid? A. Aldosterone B. Cortisol C. Corticosterone D. Testosterone

Plasma renin activity (PRA) measurements are usually made by measuring which of the following using immunoassay? A. Angiotensinogen B. Angiotensin I C. Angiotensin II D. Angiotensin-converting enzyme

What effect would a low-salt diet, upright position, and diuretics have on the following test results? A. Renin ↑, aldosterone T↑, hypernatremia, hypokalemia B. Renin ↑, aldosterone ↓, hypernatremia, hypokalemia C. Renin ↓, aldosterone ↓, hyponatremia, hyperkalemia D. Renin ↓, aldosterone ↓, hyponatremia, hyperkalemia

As a screening test for Gushing syndrome, the physician wishes to see whether a patient exhibits normal diurnal rhythm in his or her cortisol secretion. At what time should the specimens be drawn for plasma cortisol determination? A. 6 A.M., 2 P.M. B. 8 A.M.,4 P.M. C. 12 noon, 6 P.M. D. 12 noon, 12 midnight

A patient is suspected of having Addison disease. His symptoms are weakness, fatigue, loss of weight, skin pigmentation, and hypoglycemia. His laboratory tests show low serum sodium and chloride, elevated serum potassium, and elevated urine sodium and chloride levels. The serum cortisol level is decreased and the plasma ACTH is increased. To make a definitive diagnosis, the physician orders an ACTH stimulation test, and serum cortisol levels are measured If the patient has primary hypoadrenocortical function (Addison disease), what would be the expected level of serum cortisol following stimulation? If the patient has hypopituitarism and secondary hypoadrenocortical function, what would be the expected level of serum cortisol following stimulation? A. Increase from baseline; decrease from baseline B. Decrease from baseline; increase from baseline C. Slight increase from baseline; no change from baseline D. No change from baseline; slight increase from baseline

What does the concentration of urinary free cortisol mainly reflect? A. Total serum cortisol B. Conjugated cortisol C. Unbound serum cortisol D. Protein-bound serum cortisol

A 30-year-old woman is admitted to the hospital. She has truncal obesity, buffalo humpback, moon face, purple striae, hypertension, hyperglycemia, increased facial hair, acne, and amenorrhea. The physician orders endocrine testing. The results are as follows: Urine free cortisol—increased Serum cortisol (8 A.M.)—increased Plasma ACTH—decreased Dexamethasone suppression test: Overnight low dose—no suppression of serum cortisol High dose—no suppression of serum cortisol What is the most probable diagnosis? A. Pituitary adenoma B. Ectopic ACTH lung cancer C. Adrenocortical carcinoma D. Addison disease

Which of the following is the most common cause of the adrenogenital syndrome called congenital adrenal hyperplasia, and which test is used for its diagnosis? A. 17a-Hydroxylase deficiency; progesterone assay B. 21-Hydroxylase deficiency; 17a-hydroxyprogesterone assay C. 3B-Hydroxysteroid dehydrogenaseisomerase deficiency; 17a-hydroxypregnenolone assay D. 11 (3-Hydroxylase deficiency; 11-deoxycortisol assay

Which of the following is the most potent androgen? A. Androstenedione B. Dehydroepiandrosterone C. Androsterone D. Testosterone

Which of the following tissues does not secrete steroid hormones? A. Ovaries B. Pituitary gland C. Testes D. Adrenal cortex

Which of the following is the most potent estrogen and is considered to be the true ovarian hormone? A. Estriol (E3) B. Estrone (E1) C. 17p-Estradiol (E2) D. 16a-Hydroxyestrone

During pregnancy in the second trimester, human chorionic gonadotropin (hCG) levels ____ and progesterone and estriol levels _____ A. Increase,increase B. Increase, decrease C. Decrease, increase D. Decrease, decrease

Which of the following is not quantified in the triple test for Down syndrome? A. a1-Fetoprotein B. Unconjugated estriol C. Progesterone D. Human chorionic gonadotropin

Because of infertility problems, a physician would like to determine when a woman ovulates. The physician orders serial assays of plasma progesterone. From these assays, how can the physician recognize when ovulation occurs? A. After ovulation, progesterone rapidly increases. B. After ovulation, progesterone rapidly decreases. C. Right before ovulation, progesterone rapidly increases. D. There is a gradual, steady increase in progesterone throughout the menstrual cycle

The placenta secretes numerous hormones both protein and steroid. Which of the following hormones is not secreted by the placenta? A. Human chorionic gonadotropin (hCG) B. Estrogen C. Human placental lactogen (HPL) D. Luteinizing hormone (LH)

During pregnancy, estriol is synthesized in the placenta from _______ formed in the ________. A. Estradiol, mother B. Estradiol, fetus C. 16a-Hydroxy-DHEA-S.mother D. 16a-Hydroxy-DHEA-S.fetus

What percentage decrease in plasma or urinary estriol, in comparison with the previous day’s level, is considered significant during pregnancy? A. 5 B. 10 C. 25 D. 40

Which of the following compounds is not a precursor of the estrogens? A. Progesterone B. Testosterone C. Cholesterol D. Aldosterone

When do the highest levels of gonadotropins occur? A. During the follicular phase of the menstrual cycle B. During the luteal phase of the menstrual cycle C. At the midpoint of the menstrual cycle D. Several days prior to ovulation

What would be an example of ectopic hormone production? A. Prolactin production by pituitary tumors B. Calcitonin production by thyroid tumors C. Growth hormone production by lung tumors D. Cortisol production by adrenal tumors

Which of the following hormones initiates its response by binding to cytoplasmic receptors? A. Estradiol B. Epinephrine C. Growth hormone D. Follicle-stimulating hormone

The adrenal medulla secretes which of the following in the greatest quantity? A. Metanephrine B. Norepinephrine C. Epinephrine D. Dopamine