Hypothalamus-Pituitary Axis and Hormones
95 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What role does the hypothalamus play in the hypothalamus-pituitary axis?

  • It synthesizes hormones that stimulate the release of pituitary hormones. (correct)
  • It releases hormones that directly affect target organs.
  • It produces hormones that inhibit the production of insulin.
  • It acts as a storage site for pituitary hormones.

    • Which hormone is NOT released by the anterior pituitary gland?

  • Adrenocorticotropic hormone (ACTH)
  • Thyroid-stimulating hormone (TSH)
  • Follicle-stimulating hormone (FSH)
  • Anti-diuretic hormone (ADH) (correct)

    • What is the primary mechanism of action of somatropin in treating GH deficiency?

  • It competes for binding sites on IGF-1 receptors.
  • It acts as an agonist at GH receptors in tissues. (correct)
  • It mimics the action of somatostatin.
  • It inhibits insulin secretion.

    • How does mecasermin help patients who do not respond to exogenous GH therapy?

    <p>By acting as an agonist at IGF-1 receptors in various tissues.</p> Signup and view all the answers

    Which of the following hormones inhibits insulin secretion?

    <p>Insulin-like growth factor 1 (IGF-1)</p> Signup and view all the answers

    What effect does somatostatin have on growth hormone secretion?

    <p>It prevents excessive GH release.</p> Signup and view all the answers

    Which drug acts as a competitive antagonist at GH receptors?

    <p>Pegvisomant</p> Signup and view all the answers

    Which hormone is responsible for directly stimulating the release of hormones from the posterior pituitary gland?

    <p>Electrical signals</p> Signup and view all the answers

    What is the primary action of desmopressin?

    <p>Reduces urination</p> Signup and view all the answers

    Which drug is specifically used to manage hyponatremia in patients with SIADH?

    <p>Conivaptan</p> Signup and view all the answers

    What is the mechanism of action (MOA) of octreotide and lanreotide?

    <p>Agonists at SST receptors</p> Signup and view all the answers

    Which of the following is a major adverse effect of octreotide?

    <p>Bradycardia</p> Signup and view all the answers

    What side effect is specifically associated with FSH analogs in males?

    <p>Gynecomastia</p> Signup and view all the answers

    How do TSH and FSH differ in terms of regulatory hormones?

    <p>TSH is regulated by TRH, FSH by GnRH</p> Signup and view all the answers

    What condition is characterized by too much ADH production?

    <p>SIADH</p> Signup and view all the answers

    Which of the following symptoms is common in both sexes when taking FSH analogs?

    <p>Headache</p> Signup and view all the answers

    What is the first key step in the biosynthesis of thyroid hormones?

    <p>Uptake of iodine by the gland</p> Signup and view all the answers

    Which drug specifically inhibits thyroidal peroxidase (TPO)?

    <p>Methimazole</p> Signup and view all the answers

    What is the role of the Na^+/I^- symporter (NIS) in thyroid hormone biosynthesis?

    <p>Uptake of iodine into the gland</p> Signup and view all the answers

    Which of the following drugs is contraindicated in pregnancy due to the risk of ovarian hyperstimulation syndrome (OHSS)?

    <p>Leuprolide</p> Signup and view all the answers

    What is the physiological effect of T3?

    <p>Increases protein synthesis</p> Signup and view all the answers

    What is the primary mechanism of action (MOA) of cabergoline?

    <p>Dopamine D2 receptor agonist</p> Signup and view all the answers

    Which of the following thyroid hormones has the longest half-life?

    <p>T4</p> Signup and view all the answers

    Which of the following interactions is relevant for cabergoline?

    <p>Contraindicated with dopamine antagonists</p> Signup and view all the answers

    How does Propylthiouracil interfere with thyroid hormone biosynthesis?

    <p>Inhibits thyroidal peroxidase and deiodination</p> Signup and view all the answers

    What type of receptor does TSH bind to in the thyroid gland?

    <p>G protein-coupled receptor</p> Signup and view all the answers

    Which condition is conivaptan primarily used to treat?

    <p>Hyponatremia</p> Signup and view all the answers

    Which drug inhibits thyroidal peroxidase and has a potency less than methimazole?

    <p>Propylthiouracil</p> Signup and view all the answers

    Which hormone is more potent than T4?

    <p>T3</p> Signup and view all the answers

    What is a significant side effect of using drugs that increase renal excretion of water, such as conivaptan?

    <p>Electrolyte imbalances</p> Signup and view all the answers

    How does desmopressin exert its pharmacological effects?

    <p>Agonizes V2 vasopressin receptors</p> Signup and view all the answers

    What is the primary pharmacological benefit of liothyronine?

    <p>Treats hypothyroidism</p> Signup and view all the answers

    Which other drug has similar clinical usefulness to cabergoline?

    <p>Bromocriptine</p> Signup and view all the answers

    What is a common adverse effect associated with long-term use of thyroid supplements?

    <p>Osteoporosis</p> Signup and view all the answers

    Which drug is characterized as 20% T3 and 80% T4 hormone?

    <p>Liotrix</p> Signup and view all the answers

    What distinguishes desmopressin's effects from those of conivaptan?

    <p>Desmopressin increases fluid retention while conivaptan increases fluid excretion</p> Signup and view all the answers

    What effect does propylthiouracil have on warfarin effectiveness?

    <p>Decreases warfarin effectiveness</p> Signup and view all the answers

    How does potassium iodide function in relation to iodide transport?

    <p>Inhibits iodide transport</p> Signup and view all the answers

    What is the primary mode of action of methimazole?

    <p>Inhibits thyroidal peroxidase only</p> Signup and view all the answers

    When are beta-blockers typically used in patients with thyroid disorders?

    <p>To manage symptoms of hyperthyroidism</p> Signup and view all the answers

    Which drug is known to be administered subcutaneously due to potential adverse effects when given intravenously?

    <p>Mecasermin</p> Signup and view all the answers

    Which drug enhances the hypoglycemic effects of other diabetic agents?

    <p>Mecasermin</p> Signup and view all the answers

    What is a major side effect commonly associated with Cabergoline?

    <p>Nausea and vomiting</p> Signup and view all the answers

    Which of these drugs is contraindicated in pregnant patients?

    <p>Goserelin</p> Signup and view all the answers

    How do Nafarelin and Goserelin primarily differ in administration?

    <p>Nafarelin is a nasal spray; Goserelin is a subcutaneous implant</p> Signup and view all the answers

    Which two drugs are referred to as GnRH receptor super agonists?

    <p>Leuprolide and Goserelin</p> Signup and view all the answers

    What endocrine effect results from the use of Somatropin and Mecasermin?

    <p>Inhibition of insulin secretion</p> Signup and view all the answers

    What is the pharmacological action of Degarelix?

    <p>It is an antagonist that reduces LH, FSH, and gonadal steroids production.</p> Signup and view all the answers

    Which drug inhibits the conversion of T4 to T3 in peripheral tissues?

    <p>Propylthiouracil</p> Signup and view all the answers

    Which thyroid hormone has the shortest half-life?

    <p>TSH</p> Signup and view all the answers

    Which of the following is NOT a physiological effect of T3?

    <p>Stimulates the thyroid gland to produce and release T3 and T4</p> Signup and view all the answers

    Which drug is more potent in inhibiting thyroidal peroxidase?

    <p>Methimazole</p> Signup and view all the answers

    Which thyroid hormone binds to nuclear receptors?

    <p>Both T3 and T4</p> Signup and view all the answers

    Which of the following statements is TRUE regarding the mechanism of action of Propylthiouracil?

    <p>It inhibits both thyroidal peroxidase and 5' deiodination activity</p> Signup and view all the answers

    Which of the following steps in thyroid hormone biosynthesis is directly inhibited by Methimazole?

    <p>Oxidation of iodide</p> Signup and view all the answers

    Which of the following statements is FALSE regarding the physiological effects of TSH?

    <p>It increases basic metabolic rate</p> Signup and view all the answers

    Which of the following drugs is specifically used to treat hyponatremia caused by SIADH?

    <p>Conivaptan</p> Signup and view all the answers

    Which of the following is a common adverse effect associated with both octreotide and lanreotide?

    <p>Hypoglycemia</p> Signup and view all the answers

    What is the primary mechanism of action of desmopressin in treating diabetes insipidus?

    <p>Increasing renal water reabsorption</p> Signup and view all the answers

    Which of the following hormones is regulated by thyrotropin-releasing hormone (TRH)?

    <p>TSH</p> Signup and view all the answers

    Which of the following side effects associated with FSH analogs is specific to males?

    <p>Gynecomastia</p> Signup and view all the answers

    What is the main pharmacological difference between desmopressin and conivaptan?

    <p>Desmopressin acts on ADH receptors, while conivaptan blocks ADH receptors</p> Signup and view all the answers

    What is the primary function of octreotide and lanreotide in the body?

    <p>Acting as agonists at somatostatin receptors</p> Signup and view all the answers

    How does conivaptan help correct hyponatremia in patients with SIADH?

    <p>By reducing inappropriate water retention</p> Signup and view all the answers

    Which of the following drugs used to treat hypothalamic/pituitary disorders inhibits insulin secretion and hepatic glucose production?

    <p>Somatropin</p> Signup and view all the answers

    Which drug, when used to treat a hypothalamic/pituitary endocrine disorder, is most likely to cause significant hypoglycemia if not taken with a snack or small meal?

    <p>Mecasermin</p> Signup and view all the answers

    Which of the following is a D2 receptor agonist with the highest selectivity?

    <p>Cabergoline</p> Signup and view all the answers

    What is the primary role of the hypothalamus in the regulation of the pituitary gland?

    <p>Producing hormones to stimulate or inhibit the pituitary.</p> Signup and view all the answers

    Which of the following best describes the function of hormones released from the anterior pituitary gland?

    <p>To act on specific endocrine glands/tissues to produce biological effects.</p> Signup and view all the answers

    Which of the following statements accurately describes the use of subcutaneous administration for a hypothalamus/pituitary drug?

    <p>Subcutaneous administration of mecasermin reduces the risk of adverse effects compared to intravenous administration.</p> Signup and view all the answers

    In the context of treating hypothalamic/pituitary disorders, which drug has a mechanism of action that involves reducing endogenous production of LH and FSH?

    <p>Degarelix</p> Signup and view all the answers

    What is the primary therapeutic target of mecasermin administration?

    <p>Insulin-like growth factor 1 (IGF-1) receptors in various tissue.</p> Signup and view all the answers

    How does pegvisomant work to treat conditions like acromegaly or gigantism?

    <p>By competitively blocking growth hormone (GH) from binding its receptor.</p> Signup and view all the answers

    Which of the following best differentiates goserelin from leuprolide?

    <p>Goserelin is contraindicated during pregnancy whereas leuprolide is not.</p> Signup and view all the answers

    Which statement accurately describes the relationship between Nafarelin and Goserelin?

    <p>Both Nafarelin and Goserelin are GnRH receptor super agonists, but they differ in terms of common routes of administration.</p> Signup and view all the answers

    Which of these describes the action of somatostatin (SST)?

    <p>Binding to SST receptors and preventing excess growth hormone release</p> Signup and view all the answers

    What distinguishes the mechanism of action of octreotide from that of pegvisomant?

    <p>Octreotide mimics somatostatin, while pegvisomant blocks the active site at GH.</p> Signup and view all the answers

    Which of the following drugs is most likely to cause nausea, vomiting, and orthostatic hypotension?

    <p>Cabergoline</p> Signup and view all the answers

    If a patient is unresponsive to exogenous growth hormone (GH) therapy, which drug should be considered?

    <p>Mecasermin</p> Signup and view all the answers

    How does IGF-1 impact glucose homeostasis?

    <p>By inhibiting insulin secretion and hepatic glucose production.</p> Signup and view all the answers

    Which of the following best describes the pharmacokinetic property of cabergoline?

    <p>It undergoes extensive hepatic hydrolysis and has a long half-life of approximately 65 hours.</p> Signup and view all the answers

    Which drug is an antagonist at both V1a and V2 vasopressin receptors?

    <p>Conivaptan</p> Signup and view all the answers

    Which drug has increased selectivity for D2 dopamine receptors and is used in the treatment of hyperprolactinemia?

    <p>Cabergoline</p> Signup and view all the answers

    What is the primary effect of desmopressin on renal function?

    <p>Decreased water excretion by stimulating V2 receptors</p> Signup and view all the answers

    What is the major mechanism of action of GnRH super agonists such as goserelin and leuprolide?

    <p>They initially cause a surge of FSH and LH release, followed by a sustained decrease of these hormones due to receptor downregulation.</p> Signup and view all the answers

    Which of the following describes the action of conivaptan in the renal collecting duct?

    <p>It decreases water reabsorption.</p> Signup and view all the answers

    Why are urofollitropin, follitropin alpha, and menotropins contraindicated in pregnancy?

    <p>They can cause primary ovarian failure and ovarian hyperstimulation syndrome (OHSS).</p> Signup and view all the answers

    Which of the following drug interactions is NOT listed with Cabergoline?

    <p>Calcium channel antagonists such as diltiazem</p> Signup and view all the answers

    What is the primary pharmacological benefit of propylthiouracil?

    <p>To inhibit thyroid hormone production</p> Signup and view all the answers

    Which characteristic distinguishes methimazole from propylthiouracil?

    <p>Methimazole lacks the ability to inhibit 5' deiodinase</p> Signup and view all the answers

    What are the potential adverse effects associated with long-term use of thyroid supplements?

    <p>Fatigue and osteoporosis</p> Signup and view all the answers

    How does potassium iodide affect iodide transport?

    <p>It inhibits iodide transport via the NIS</p> Signup and view all the answers

    What is the mechanism of action of levothyroxine?

    <p>It acts as a ligand for TR as a T4 hormone</p> Signup and view all the answers

    Which composition characterizes liotrix?

    <p>20% T3 and 80% T4</p> Signup and view all the answers

    When are beta-blockers appropriate in the management of thyroid disorders?

    <p>To alleviate symptoms of hyperthyroidism</p> Signup and view all the answers

    Study Notes

    Hypothalamus-Pituitary Axis

    • Hypothalamus releases hormones to stimulate or inhibit pituitary gland.
    • Pituitary gland synthesizes and releases hormones acting on target organs.

    Pituitary and Hypothalamus Hormones

    • Hypothalamus: GHRH, TRH, CRH, GnRH, GnRH, TSH, dopamine
    • Anterior Pituitary: GH, TSH, ACTH, LH, FSH, prolactin
    • Posterior Pituitary: ADH, oxytocin
    • Hypothalamus hormones trigger anterior pituitary hormone release, and electrical signals stimulate posterior pituitary hormone release.

    Treating GH Deficiency

    • Somatropin: Agonist at GH receptors, increasing GH levels.
    • Mecasermin: Agonist at IGF-1 receptors (helps non-responsive to exogenous GH therapy).
    • Mecasermin administration should be subcutaneous due to potential adverse effects if administered intravenously.

    Treating Acromegaly/Gigantism

    • Somatostatin Analogs (Octreotide/Lanreotide): SST receptor agonists, preventing excessive GH release.
    • Pegvisomant: Competitive GH receptor antagonist, blocking GH binding.

    IGF-1

    • Insulin-like growth factor 1.
    • Inhibits insulin secretion, hepatic glucose production.

    SST

    • Somatostatin, binds to SST receptors, preventing GH release.

    Mecasermin MOA

    • Agonist at IGF-1 receptors in liver, bone, etc, helping non-responsive to exogenous GH therapy patients.

    Drugs Affecting Glycemic Control

    • Somatropin and Mecasermin can interfere with glycemic control.
    • Mecasermin has a high likelihood of causing hypoglycemia.
    • Mecasermin stimulates IGF-1, which inhibits insulin secretion and hepatic glucose production thereby enhancing hypoglycemic effects of other diabetic agents.

    Bromocriptine and Cabergoline

    • Used to control prolactinemia.
    • Bromocriptine: Slightly selective D2 receptor agonist.
    • Cabergoline: Higher D2 selectivity, returns normal prolactin levels.
    • Cabergoline has longer half-life, potential for nausea/vomiting/orthostatic hypotension.

    Goserelin/Leuprolide/Degarelix

    • GnRH receptor super agonists (goserelin and leuprolide).
    • Degarelix is a GnRH receptor antagonist.
    • Goserelin is contraindicated in pregnant patients.
    • Nafarelin is similar to goserelin but is given as a nasal spray.

    Cabergoline and Bromocriptine

    • Both are used for hyperprolactinemia, with cabergoline having higher selectivity for D2 dopamine receptors.

    Desmopressin and Conivaptan

    • Desmopressin (DDAVP): V2 vasopressin receptor agonist, reducing water excretion in renal collecting ducts, increasing Factor VIII and von Willebrand factors.
    • Conivaptan (Vaprisol): V1a and V2 vasopressin antagonist, increasing water excretion in the collecting ducts.

    Octreotide and Lanreotide

    • Somatostatin analogs, SST receptor agonists (1-5 and 2/5 respectively).

    Hyponatremia Treatment

    • Conivaptan is used to treat hyponatremia by reducing inappropriate water retention.

    TSH/FSH/LH

    • TSH: Released by TRH, regulates thyroid hormone production.
    • FSH/LH: Released by GnRH, stimulate ovarian/testicular hormone production.
    • TSH, FSH, LH are anterior pituitary hormones.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    IMCP Exam 2 Study Guide PDF

    Description

    Explore the critical functions of the hypothalamus and pituitary gland in hormone regulation. This quiz covers key hormones, their effects, and treatments for conditions like GH deficiency and acromegaly. Test your knowledge on hormone action and therapeutic approaches.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser