Weekly Quizzes Flashcards
The five classes of steroid hormones (progestagens, mineralocorticoids, glucocorticoids, androgens, and estrogens):
A.are stored in the cells before release
B.bind G-protein Coupled Receptors
C.are each synthesized by unique enzymes
D.use carrier proteins for transport in the serum
E.all has the same number of carbons
Answer Key: D
Feedback:
a) is incorrect because steroid hormones are lipophillic and readily cross the plasma membrane. They are not stored.
b) is incorrect. ATCH/LH/FSH use G-protein coupled receptors to initiate steroid hormone biosynthesis in their target tissues (adrenal/gonadal cells). Steroid hormones use intracellular receptors that act as transcription factors.
c) is not correct because many of the enzymes used to synthesize the various classes are redundant.
*d) is correct. Because steroid hormones are lipophillic and hydrophobic, they need carrier proteins be to transported in the blood.
e) is not correct. Progestagens (C21), mineralocorticoids (C21), glucocorticoids (C21), androgens (C19), estrogens (C18).
A 22-year-old woman has been taking daily doses of prednisone for several years to suppress her sarcoidosis, a potentially life-threatening a multisystem granulomatous inflammatory disease. Which of the following side effects is she MOST LIKELY to experience?
A.acromegaly
B.hypoglycemia
C.hyponatremia
D.lymphocytosis
E.osteoporosis
Answer Key: E
Feedback:
Glucocorticoids have nothing to do with acromegaly so “A” is incorrect.
Glucocorticoids cause HYPERglycemia, so “B” is obviously incorrect.
Glucocorticoids cause sodium retention, i.e. hypernatremia, so “C” is incorrect.
Glucocorticoid are immunosuppressive and caused decreased lymphyocyte counts so “D” is incorrect.
Glucocorticoids stimulate osteoclast and inhibit osteoblast activities, so “E” is the only correct answer.
Which of the following statements is CORRECTLY paired with the associated corticosteroid or corticosteroid antagonist?
A.dexamethasone – potent, long-acting synthetic glucocorticoid with low mineralocorticoid activity
B.beclomethasone – corticosteroid antagonist used for induction of early-term abortions
C.cortisone – endogenous glucocorticoid that is inactivated by 11β-hydroxysteroid dehydrogenase (HSD11B2)
D.eplerenone – inhaled steroid used for treatment of asthma
E.mifepristone – corticosteroid antagonist used for treatment of hypertension
Answer Key: A
Feedback:
Dexamethasone is a high affinity, long-acting agonist with low affinity for the mineralocorticoid receptor. “A” is correct.
Beclomethasone is used primarily as an inhaled steroid because of its extensive hepatic metabolism. It is mifepristone that is used to induce early-term abortions. “B” and “E” are therefore incorrect.
Cortisol, not cortisone, is the main endogenous glucocorticoid. Cortisone is inactive and must be activated by 11βHSD1. “C” is therefore incorrect as well.
Eplerenone is a specific mineralocorticoid antagonist used for treating hypertension. It has no glucocorticoid activity and no effect in asthma. “D” is incorrect. “E” is incorrect. Mifepristone in an antagonist at both the progesterone receptor and the glucocorticoid receptor that is primarily used to induce early-term abortion; it may be used to treat Cushing’s Syndrome, but it is not used to treat hypertension.
Your patient comes to you complaining that over the last year he has noticed stiffness in his joints and a deeper voice. Interestingly, he says his feet and nose seem to be getting bigger. You do a blood test and it reveals that his
A.Growth hormone levels are below normal.
B.Somatostatin levels are below normal.
C.Prolactin levels are above normal.
D.Growth hormone releasing hormone levels are below normal.
E.Thyroid releasing hormone levels are below normal.
Answer Key: D
Feedback: Ans. D. The patient is suffering from an excess of growth hormone, most likely from a pituitary tumor, so A is incorrect. Somatostatin levels will go up to attempt to inhibit the release of GH, so B is incorrect. Prolactin and TRH should not be involved in the tumor secretion so C and E are incorrect. Growth hormone will normally inhibit GHRH so GHRH should be very low. However, the tumor is not dependent on GHRH for stimulation of secretion of GH. GHRH secretion goes down, but without effect on the tumor cells. D is correct.
A 35-year-old woman presents with an elongated mandible and an unusually broad nose. She also complains of joint stiffness and carpal tunnel syndrome. She tells you that she has been lactating even though she has never given birth. Laboratory tests reveal that she has elevated growth hormone and prolactin levels. Which of the follow drugs would most likely cause a lowering of her GH and prolactin levels?
A.glucagon
B.somatropin
C.pegvisomant
D.bromocriptine
E.mecasermin
Answer Key: D
Feedback:
a) Glucagon is incorrect because glucagon acts on the liver to increase gluconeogenesis and glycogenolysis resulting an increased blood glucose levels. This would do nothing to alter GH and prolactin levels.
b) Somatropin is incorrect. Somatropin is GH, and its administration would worsen the problem.
c) Pegvisomant is incorrect. Although pegvisomant is an effective GH antagonist and would improve the symptoms of acromegaly, it would not improve the galactorrhea due to excess prolactin.
d) Bromocriptine is CORRECT. Most pituitary adenomas that secrete both GH and prolactin express D2 dopamine receptors. Bromocriptine is a potent D2 agonist that will inhibit the release of both GH and prolactin.
e) Mecasermin incorrect. Mecasermin is an IGF-1 (somatomedin C) analog that stimulates growth (growth of cartilage in adults). It would make the symptoms of GH excess even worse
Of the following hormones, which one is most likely to act through a mechanism that involves increased binding of its receptors to DNA?
A.progesterone
B.insulin
C.corticotropin releasing hormone
D.melatonin
E.luteinizing hormone
Answer Key: A
Feedback: a. correct –progesterone, a steroid hormone, is lipid soluble and readily diffuse through the cell membrane into target cells where it acts in the nucleus, via nuclear receptors, to regulate gene expression. The rest of the choices (b – e) are water soluble hormones that are excluded by the cell plasma membrane and therefore act on cell surface receptors.
b. incorrect – insulin is a water soluble protein hormone that acts through cell-surface receptors
c. incorrect - corticotropin releasing hormone is a water soluble protein hormone that acts through cell-surface receptors
d. melatonin is a water soluble derivative of an amino acid that acts through cell-surface receptors
e. luteinizing hormone is a water soluble glycoprotein hormone that acts through cell-surface receptors
During an examination of a pregnant patient in her first trimester, you detect that her heart rate is rapid, her skin is hot and sweaty, and she has a symmetrical goiter. Her blood tests indicate that she has low levels of TSH and high levels of free T4. What would be the best course of treatment of this patient?
A.octreotide to increase TSH release from her anterior pituitary gland
B.sodium levothyroxine to bring about a negative feedback inhibition of hypothalamic TRH release
C.propylthiouracil to inhibit thyroid peroxidasse
D.immediate radioactive iodine (131I) treatment, followed by levothyroxine
E.thyroidectomy
Answer Key: C
Feedback:
A. Octreotide is a somatostatin analogue used to suppress growth hormone secretion.
B. Levothyroxine is synthetic thyroid hormone; the patient already has high T4 levels, thus further supplementation would exacerbate the problem.
C. Propylthiouracil is the preferred anti-thyroid peroxidase treatment for pregnant hyperthyroid patients during the first trimester because it does not pass the placenta as efficiently as methimazole. The lowest dose possible is suggested to avoid suppressing the thyroid hormone production in the developing fetus.
D. Radioactive iodine is never recommended for pregnant women.
E. Who do you think you are? A surgeon? Surgery may cause loss of the fetus.
Hyperprolactinemia may be caused by
A.primary hyperthyroidism.
B.bromocriptine therapy.
C.excess hypothalamic dopamine release.
D.haloperidol therapy
E.low serum estrogen.
Answer Key: D
Feedback: a. incorrect. TRH could stimulate an elevation of prolactin levels, but high levels of T3 and T4 that occur in hyperthyroidism would decrease TRH (negative feedback).
b. incorrect. Bromocriptine is a D2 dopamine receptor agonist. Since dopamine acting at a D2 dopamine receptor inhibits prolactin synthesis and release, bromocriptine would lower, not raise, prolactin levels.
c. incorrect. Excess hypothalamic dopamine would decrease prolactin synthesis and release (just like bromocriptine).
d. correct. Haloperidol is an antipsychotic that blocks D2 dopamine receptors. So, haloperidol would block the inhibitory influence of endogenous dopamine resulting hyperprolactinemia.
e. incorrect. High levels of estrogen enhance the release of prolactin toward the end of pregnancy. So, low serum estrogen would tend to lower serum prolactin.
The ability of 1,25-(OH)2vitamin D3 to protect against hypocalcemia and osteoporosis results primarily from its action on the
A.kidney to increase the reabsorption of calcium.
B.parathyroid glands to increase the secretion of parathyroid hormone.
C.thyroid to increase the secretion of calcitonin.
D.intestine to increase the absorption of calcium.
E.kidney to increase 1-hydroxylase activity.
Answer Key: D
Cirrhosis of the liver results in the continuous leakage of vascular fluid into the abdomen (ascites) and thereby a decrease in effective blood volume. Physiologic responses attempting to correct for this condition include
A.increased negative feedback by potassium on renin secretion.
B.increased production of angiotensin II.
C.decreased secretion of the adrenal catecholamines.
D.decreased secretion of antidiuretic hormone.
E.increased release of atrial natriuretic peptide.
Answer Key: B
In a normal individual, consumption of a meal consisting exclusively of protein will
A.increase the secretion of glucagon.
B.inhibit the mobilization of hepatic glycogen.
C.decrease the secretion of insulin.
D.decrease the secretion of cortisol.
E.decrease blood levels of glucose.
Answer Key: A
A patient presenting with polyuria and polydipsia fails to concentrate their urine in response to fluid deprivation or the administration of ADH. Which of the following conditions is most consistent with these observations?
A.Compulsive water drinking
B.Neurohypophyseal diabetes insipidus
C.Nephrogenic diabetes insipidus
D.Absence of renin secretion
E.A defective thirst sensing mechanism
Answer Key: C
You are evaluating a 13-year-old girl who has a 6-year history of type 1 diabetes. She has a known history of noncompliance with her insulin therapy. She complains of abdominal pain, and she appears mildly dehydrated. A serum glucose level is 650 mg/dL (36.1 mmol/L). Her urinalysis is positive for glucose and ketones, and a venous pH is 7.20. Of the following, the most appropriate initial management step is to:
A.Administer a bolus of 10 to 20 mL/kg normal saline.
B.Administer an intravenous bicarbonate infusion.
C.Begin an insulin drip at a rate of 0.5 U/kg per hour.
D.Obtain a glycosylated hemoglobin level.
E.Start two times maintenance fluid requirements with normal saline and potassium.
Answer Key: A
Feedback: A is correct as a 10-20 cc/kg bolus to given over an hour is the recommended initial therapy in a child with DKA in order to begin to correct their dehydration. This will also likely slightly improve their hyperglycemia as well.
B is incorrect as intravenous bicarbonate infusion is contraindicated in the management of DKA
C is incorrect as after the bolus, an insulin drip at 0.1 units/kg per hour should be started
D is incorrect as a glycosylated hemoglobin level will not assist in the acute management of this patient.
E is incorrect as an initial isotonic fluid bolus should be initiated prior to starting maintenance fluids
Rapid increases in blood levels of angiotensin I, angiotensin 2, glucagon, antidiuretic hormone, epinephrine, and adrenocorticotropin (ACTH) result from
A.the rapid loss of two liters of blood.
B.assumption of the prone position.
C.infusion of two units of physiologic saline.
D.treatment with a drug that inhibits renin activity.
E.treatment with a drug that blocks angiotensin II receptors.
Answer Key: A
Ketoacidosis is the extreme clinical condition of
A.a high protein diet.
B.Cushing’s syndrome.
C.Type I diabetes mellitus.
D.Type II diabetes mellitus.
E.catecholamine excess.
Answer Key: C
A 45-year-old female is 5 feet 4 inches tall and weighs 255 lb. Her fasting blood glucose is 225 mg/dl. She is already being treated with a sulfonylurea to stimulate release of insulin. Which of the following drugs might you add to her drug regimen that would act by inhibiting gluconeogenesis?
A.glucagon
B.metformin
C.acarbose
D.sitagliptin
E.canagliflozen
Answer Key: B
Feedback: a) incorrect. Glucagon increases gluconeogenesis and glycogenolysis.
b) correct. Metformin inhibits gluconeogenesis, lowers blood glucose, but never causes hypoglycemia.
c) incorrect. Acarbose is an alpha-glucosidase inhibitor that slows the breakdown of carbohydrates to glucose in the GI tract. It reduces glucose uptake.
d) incorrect. Sitagliptin inhibits the breakdown of endogenous glucagon-like peptide 1 (GLP-1) allowing GLP-1 to cause a more profound and longer lasting stimulation of insulin release.
e) incorrect. Canagliflozen inhibits the sodium-glucose co-transporter-2 in the proximal tubules of the kidney. This inhibitory action of canagliflozen reduces the amount of filtered glucose that is taken back into the blood and causes an increased loss of glucose in urine.
The physiologic relationship that exists between the regulation of cortisol and ACTH is analogous to the relationship that exists between
A.T3 and TSH.
B.epinephrine and ACTH.
C.somatostatin and insulin.
D.PTH and Ca2+.
E.somatostatin and growth hormone.
Answer Key: A
You are seeing a 9-year-old boy who was diagnosed with type 1 diabetes 2 years ago. He currently receives long acting insulin every night at 2100 and ultra short acting insulin prior to meals for carbohydrate coverage and blood glucose correction. As part of your evaluation, you ask to see his blood glucose diary. You note that most of his readings prior to dinner are in the mid 200’s. His blood glucose readings prior to breakfast and lunch, and before bed are in the low 100’s. Which of the following management options is the best?
A.Decrease the amount of insulin he gets with dinner
B.Increase the amount of insulin he gets with lunch
C.Increase the amount of insulin he gets with breakfast
D.Obtain a HgA1C level, and if it is < 9, continue the current insulin regimen.
E.Split his long acting insulin and give half at 2100 and half at lunchtime
Answer Key: B
Feedback:
A is incorrect as decreasing the amount of insulin with dinner would likely lead to high blood glucose levels at bed time
B is correct because his high blood glucose levels prior to dinner combined with normal blood glucose levels prior to lunch, suggest the patient has not been given enough insulin to cover his carbs at that meal
C is not correct as his breakfast time insulin seems appropriate given his normal blood glucose levels prior to lunch
D is not correct as the goal Hgb A1c for this age is < 7.5
E is incorrect as splitting his long acting insulin would not necessarily improve his dinner time blood glucose
The synthesis and accumulation of glycogen in the vagina is stimulated by
A.androgens from the adrenal gland.
B.estrogen
C.oxytocin
D.progesterone.
E.gonadotropin releasing hormone.
Answer Key: B
Adult members of a large HMO were screened for diabetes at a primary
care clinic, and the disease was identified among 4.7% of adult
members. The screening test had sensitivity of 0.91, specificity of
0.99, and positive predictive value of 0.82. If the screening program
was repeated in a high-risk population with diabetes prevalence of
15%, which of the following would likely be observed:
A.Increased sensitivity, decreased specificity
B.Decreased sensitivity, increased specificity
C.Increased positive predictive value, no change to sensitivity or specificity
D.Decreased positive predictive value, no change to sensitivity or specificity
E.No change to sensitivity, specificity or positive predictive value
Answer Key: C
Feedback: a. Incorrect: Sensitivity and specificity are characteristics of the
test, and do not depend on prevalence.
b. Incorrect: Sensitivity and specificity are characteristics of the
test, and do not depend on prevalence.
c. Correct: Positive predictive value increases with increasing
prevalence. Sensitivity and specificity are characteristics of the
test, and do not depend on prevalence.
d. Incorrect: Positive predictive value increases with increasing
prevalence. Sensitivity and specificity are characteristics of the
test, and do not depend on prevalence.
e. Incorrect: Positive predictive value increases with increasing
prevalence. Sensitivity and specificity are characteristics of the
test, and do not depend on prevalence.
A 46 year old female presents to the emergency department with severe right lower quadrant pain that has been increasing for the past 12 hours. Her physical exam is significant for a temperature of 100.8, a diffusely tender abdominal and pelvic exam with pain localizing most to the right lower quadrant. A CT reveals a right pelvic mass with inflammatory stranding but neither the ovary nor the appendix can be clearly delineated. The patient is taken to surgery where an acutely inflamed appendix is noted to be adhered to the right ovary at the pelvic brim. Which of the following structures is least likely to pose a challenge in performing the necessary surgery?
A.Infundibulopelvic ligament
B.ureter
C.external iliac artery
D.distal ileum
E.sigmoid colon
Answer Key: E
Feedback: a. incorrect – The infundibulopelvic ligament is a peritoneal fold that contains the ovarian vessels, nerves, and lymphatics. It passes from the upper pole of the ovary, usually lateral to the ureter, over the pelvic brim and external iliac vessels to merge with the peritoneum over the psoas major. Because of its course, it is likely to be encountered when operating near the pelvic brim.
b. incorrect – As the ureter descends to the pelvis it lies posterior to the parietal peritoneum and just superior to the pelvic brim, the root of the mesentery of the small intestine. It is crossed on its anterior surface by the ovarian vessels traveling in the infundibulopelvic ligament.
c. incorrect – The infundibulopelvic ligament and ureter both pass into the pelvis at the level of the bifurcation of the common iliac artery, therefore any structures adhered in this region will likely be in close proximity to the common or external iliac arteries.
d. Incorrect – The distal ileum is immediately adjacent to the cecum and appendix. In the context of inflammation, it will commonly be adherent to the structures at the pelvic brim.
e. correct – It is possible that the sigmoid colon, particularly a redundant sigmoid, could be adherent to the right pelvic sidewall in the setting of scar tissue or inflammation. It is much more common for the sigmoid to impact surgeries in the left pelvis; therefore of the choices given, the sigmoid colon is least likely to pose a challenge in this surgery.
As compared to levels normally present in the early follicular phase, low levels of
estrogen and progesterone, and very high levels of LH and FSH are found in a female who is
A.in the postmenopausal state.
B.entering puberty.
C.undergoing ovulation.
D.a newborn.
E.receiving a drug that stimulates estrogen receptors.
Answer Key: A
Feedback: a. correct – this is the condition that exists after ovarian follicles have been depleted and the production of estrogen and progesterone is essentially reduced to zero. Accordingly, the pituitary is relieved of steroid hormone negative feedback and the secretion of LH and FSH is therefore unrestrained.
b. incorrect – at the time of puberty levels of LH, FSH, estrogen and progesterone are all rising to normal adult levels
c. incorrect – at ovulation to levels of estrogen, LH and FSH are all elevated, marking the follicular growth that has occurred during the follicular phase and the ovulatory surge of the gonadotropins.
d. incorrect – in a newborn all activities of the hypothalamic-pituitary-gonadal axis is profoundly suppressed.
e. incorrect – a drug that stimulates estrogen receptors would inhibit LH and FSH secretion via conventional negative feedback mechanisms. As a consequence, the output of ovarian estrogen and progesterone would decline and blood levels of these steroids would be reduced
The ovary of a newborn baby girl contains oocytes that are
A.haploid and may contain the Y chromosome.
B.undergoing mitosis
C.not surrounded by follicular cells.
D.surrounded by a single layer of simple, squamous cells.
E.arrested in metaphase of meiosis II.
Answer Key: D
Feedback: Answer d is correct
