Hypothalamus and Pituitary Gland

Is the most dominant portion of the entire endocrine system.
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Terms in this set (117)
Is the most dominant portion of the entire endocrine system.
The hypothalamus-pituitary unit
True/False - The output of the hypothalamus-pituitary unit regulates the function of the thyroid, adrenal and
reproductive glands and also controls somatic growth, lactation, milk secretion and water metabolism.
True
True/False - Hypothalamic function depends on the pituitary and the anatomical organization of the hypothalamus-pituitary unit reflects this relationship.
False (Pituitary ; hypothalamus)
An organ located in the limbic system of the brain.

Almond-sized, cone-shaped gland, located below the thalamus and above the pituitary gland and brain stem.

It is responsible for controlling pituitary hormone secretion.
Hypothalamus
Hypothalamus secretes its peptide hormones, also known as releasing hormones either into:
a. into the short private portal system to directly impinge on the anterior pituitary

b. directly into the general circulation
True/False - The pituitary is considered the link between nervous system and endocrine system.
False (Hypothalamus)
It produces releasing and inhibiting hormones, which stop and start the production of hormones throughout the body.
Hypothalamus
True/False - The hypothalamus is involved with the maintenance of homeostasis.
True
Also called arginine vasopressin (AVP).
ADH
The hormone that regulate water levels in the body, including blood volume and blood pressure.
ADH / AVP
A condition wherein the body is unable to put out dilute urine, perturbs fluid (and electrolyte) balance, and causes nausea, vomiting, muscle cramps, confusion and convulsions. This syndrome may occur in association with oat-cell lung cancer, pancreatic cancer, prostate cancer, and Hodgkin's disease aswell as a number of other disorders.Syndrome of Inappropriate Antidiuretic Hormone (SIADH)A peptide hormone and neurotransmitter involved in the stress response.CRHA hormone that controls the body's response to physical and emotional stress, and is responsible for suppressing the appetite and stimulating anxiety.CRHTrue/False - CRH sends a message to the posterior pituitary gland to release adrenocorticotropic hormone that stimulate the adrenal glands to release corticosteroids, which help regulate metabolism and immune response.False (Anterior)The central driver of the stress hormone system is the main role of corticotropin-releasing hormone in the body which is also known as the: __________.Hypothalamic-pituitary adrenal axisTrue/False - Corticotropin-releasing hormone is also made by certain white blood cells, where it stimulates swelling or tenderness known as inflammation, particularly of the gut.TrueTrue/False - Corticotropin-releasing hormone is also produced throughout pregnancy in increasing amounts.TrueSome effects of corticotropin-releasing hormone in the brain can also be blocked by _______, a hormone produced by fat tissue.LeptinTrue/False - Decrease CRH can cause nervous problems such as clinical depression, anxiety, sleep disturbances and anorexia nervosa. May also make certain inflammatory problems worse, including rheumatoid arthritis, psoriasis, ulcerative colitis and Crohn's disease.False (Increase)Stimulates the release of hormones connected to reproductive function, puberty and sexual maturation.GnRHA deficiency of gonadotropin-releasing hormone in childhood means that the individual does not go through puberty, this is a rare genetic syndrome called ________.Kallmann's SyndromeTrue/False - Any trauma or damage to the hypothalamus can also cause a loss of gonadotropin-releasing hormone secretion which will stop the normal production of follicle stimulating hormone and luteinising hormone.TrueGHIH is also known as ________.SomatostatinA hormone that controls growth and physical development in children as well as metabolism in adults.GHRHA type of tumor that is located in abnormal / other parts of the body.Ectopic tumorsTrue/False - The consequence of too much growth hormone-releasing hormone is a rise in growth hormone levels in the bloodstream and, in many cases, atrophy of the pituitary gland.False (enlargement)A condition which is a result of excessive GH for long periods of time in which patients have swelling of the hands and feet and altered facial features. These patients also have organ enlargement and serious functional disorders such as high blood pressure, diabetes and heart disease.AcromegalyAn increase in growth hormone before children reach their final height can lead to excessive growth of long bones, resulting in the child being abnormally tall. This is commonly known as _______.GigantismTrue/False - If the hypothalamus produces too much growth hormone-releasing hormone, the production and release of growth hormone from the pituitary gland is impaired, leading to a lack of growth hormone.False (too low)A condition associated with growth failure and delayed physical maturity. In adults, the most important consequences of reduced growth hormone levels are changes in body structure (decreased muscle and bone mass and increased body fat), tiredness, being less lively and a poor health-related quality of life.Childhood onset growth hormone deficiencyA hormone that controls some human behaviors and the reproductive system. It is involved in a variety of processes, such as orgasm, regulation of body temperature, sleep cycles, and the release of breast milk.OxytocinProlactin-inhibiting hormone is also known as _______?DopamineA hormone that prompts the anterior pituitary to stimulate breast milk production through the production of prolactin.PRHA hormone that triggers the release of thyroid stimulating hormone (TSH), which stimulates release of thyroid hormones ,which regulate metabolism, energy, and growth development, also controls the cardiovascular system, brain development, muscle control.TRHA gland that is being controlled by the hypothalamus. It is also located at the base of the brain.Pituitary glandThe pituitary gland is protected by a bony strcuture called ________ (Turkish saddle - in English).Sella turcicaThe ______ is located just above the pituitary gland. It carries visual information to the brain for interpretation.Optic ChiasmThe 3 distinct parts of a pituitary gland.1. Anterior pituitary or adenophysis 2. Intermediate lobe or pars intermedialis 3. Posterior pituitary or neurophysisA condition that can alter pituitary hormone secretion and be used to test for abnormality.StressA mechanism by which by-products of end-organ endocrine glands or tissues act back, usually inhibiting, or in rare cases, enhancing, pituitary response to hypothalamic factors.FeedbackTrue/False - Cyclic fluctuations in hypothalamic hormone secretion is mediated via CNS regulation of pituitary releasing factors, and may be altered in diseaseFalse (pituitary ; hypothalamic)True/False - The endocrine system remains in equilibrium (constancy) via negative feed-back mechanisms. Also, the degree of negative feedback is always constant.False (not constant)Hormones regulated by the pituitary gland in the anterior lobe.-GH -LH -ACTH -PRL -TSH -FSHFemales: stimulates estrogen production and maturation of the ova. Males: stimulates sperm production.FSHStimulates the thyroid gland to release its hormones.TSHStimulates milk production.PRLStimulates increase in size of muscles and bones.GHFemales: stimulates ovulation and estrogen production. Males: stimulates testosterone production.LHStimulates the adrenal cortex to release its hormones.ACTHHormones regulated by the pituitary gland in the posterior lobe.-Oxytocin -ADHFemales: causes contraction of the uterus and ejection of breast milk. Males: stimulates contraction of the prostate and vas deferens during sexual arousal.OxytocinStimulates the kidneys to conserve water.ADHAnterior pituitary cell types.- Lactotrophs - Somatotrophs - Thyrotrophs - Corticotrophs - GonadotrophsThey are larger and more complex than those synthesized in the hypothalamus.Anterior Pituitary HormonesIdentify whether tropic or direct effectors. 1. GH 2. LH 3. TSH 4. PRL 5. ACTH 6. FSH1. Direct effector 2. Tropic 3. Tropic 4. Direct effector 5. Tropic 6. TropicA hormone that promotes growth (indirectly), control of protein, lipid and carbohydrate metabolism.GHMajor target organs of GH.-liver -adipose tissue -boneMajor target organ of TSH.Thyroid GlandMajor target organ of ACTH.Adrenal Gland (Cortex)Major target organ of PRL.Mammary GlandMajor target organs of LH.Ovary and TestisMajor target organs of FSH.Ovary and testisMajor target organ of ADH.KidneyMajor target organs of oxytocin.Ovary and testisOther name of growth hormone.SomatotropinIts two major actions include: 1. To stimulate production of insulin-like growth factor(IGF-1), mainly by the liver but to some extent by all tissues 2. To promote lypolysis and antagonise insulin-mediated glucose uptake, which is appropriate to the fasting state.GHTrue/False - Secretion of GH occurs in burst and intense after onset of sleep.TrueAn uncommon but important condition that is a treatable cause of growth retardation.GH DeficiencyA distinct form of childhood dwarfism that is due to a genetic defect in the GH receptor.Laron DwarfismA common disorder causing impotence in males, amenorrhea in females, and infertility and/or galactorrhea in either M/F.HyperprolactinemiaHigh PRL can be due to a pituitary tumor that secretes PRL directly (prolactinoma) or any pituitary lesion that disrupts blood flow of portal blood carrying dopamine from the hypothalamus, this incident called the _________.Stalk-effectTrue/False - The only clinical manifestation of a PRL deficiency is failure to lactate.TrueIncreased PRL secretion may also be due to except: A. Anti-dopaminergic drugs (commonly used to treat psychosis or hypertension) B. Primary hypothyroidism, where it is due to hypothalamic TRH C. Stress D. Increased dopamine productionD.A large glycoprotein hormone composed of an α and β subunit.TSHTrue/False - The α-subunit is common to all glycoprotein hormones like TSH, while the β-subunit is unique to FSH, LH and hCG.False (opposite ; beta = TSH)A hormone produced by the placenta during pregnancy.hCG (human chorionic gonadotropin)True/False - Secretion of TSH is controlled by stimulation by the hypothalamic tri-peptide TRH, while the action and secretion of TRH is inhibited by thyroid hormone.TrueLow blood levels of TSH.HyperthyroidismHigh blood levels of TSH.Primary hypothyroidismThese are glycoprotein hormones, similar in size and structure to TSH.FSH and LHTrue/False - Decreased levels of Gonadotropin are seen in ovarian failure.False (Increase)True/False - In men with azoospermia, FSH is increased, while LH decreases in response to a fall in testosterone.False (LH increases)True/False - Gonadotropin-secreting tumors of the pituitary is more common while gonadal failure secondary to decreased gonadotropin secretion is rare.False (tumor = rare ; gonadal failure = more common)A single polypeptide of 39 amino acids that stimulates adrenal glucocorticoid (but NOT minerallocorticoid) secretion.ACTHTrue/False - ACTH secretion exhibits diurnal variation, highest at 8:00 AM, lowest at midnight.TrueTrue/False - Excessive secretion of ACTH occurs with some pituitary tumors (Cushing's disease) and in primary adrenal failure (Addison's disease).TrueTrue/False - Pituitary tumours may cause visual field defects.TrueThe gold standard for the stimulation test of growth hormone. It is also used for cortisol deficiency. Using an arginine infusion for stimulation is probably as effective and other drugs used include glucagon, clonidine, and propranolol.Insulin-induced hypoglycemia testRegarded as the best test to stimulate growth hormone and ACTH secretion as long as there are no contra-indications.Insulin Stress Test or Insulin Tolerance TestMeasures the adrenal response to adrenocorticotropic hormone (ACTH).Synacthen TestAdministered as an intravenous bolus with measurements of cortisol (and for 17-hydroxyprogesterone where the test is being performed for possible congenital adrenal hyperplasia) at 0 minutes, 30 minutes, and 60 minutes.Synacthen (an ACTH analogue)A test that blocks adrenal hormone production and normal individuals respond by producing large amounts of ACTH. Lack of response indicates pituitary disease affecting ACTH production.Metyrapone TestTrue/False - Single measurement of plasma dehydroepiandrosterone sulfate levels has recently been shown to be at least a reasonable screening test for ACTH deficiency, with good sensitivity and specificity.TrueTrue/False - Gonadotropin deficiency is difficult to assess in girls prior to puberty or in boys after age 3-6 months and before puberty.TrueA test performed for gonadotropin deficiency.Gonadotropin stimulation testTrue/False - TRH stimulation test is useful in the diagnosis of central hyperthyroidism, especially if free T4 and/or TSH is low-normal.False (hypothyroidism)True/False - Prolactin deficiency can be confirmed by administering TRH or an anti-dopaminergic agent (e.g. metoclopramide) and measuring prolactin levels. Failure of the prolactin level to rise is diagnostic of prolactin deficiency.TrueTrue/False - Patients with prolactin-secreting tumours usually show little or no prolactin increase in response toTRH.TruePatients with elevated serum prolactin from other causes usually show a more normal response, with a rise in prolactin of at least 100% following TRH administration.TrueTrue/False - A single measurement of growth hormone is inadequate because growth hormone is secreted in a pulsatile manner during deep sleep.TrueIt is a sensitive screening test for acromegaly.Serum insulin-like growth factor-I (IGF-I)It a sensitive marker of growth hormone hypersecretion.Serum insulin-like growth factor-binding protein-3 (IGFBP-3)It is the single best laboratory criterion for diagnosing growth hormone.Oral Glucose Tolerance Test (OGTT)The test is useful in the assessment of precocious puberty.GnRH stimulation testAn alternative test that can accurately predict pubertal progression.Leuprorelin Acetate stimulation testA cyclic nonapeptides. Major role in labor and parturition. Has a critical role in lactation ( "let-down" reflex).OxytocinSynthetic oxytocin used in obstetrics to induce labor.PitocinA potent pressor agent and effects blood clotting by promoting factor VII release from hepatocytes and von Willebrand factor release from the endothelium.VasopressinTrue/False - Vasopressin differs from oxytocin by only 2 amino acids (phenylalanine and arginine replace isoleucine and leucine of oxytocin).TrueA type of diabetic insipidus that results from a deficiency in secretion of antidiuretic hormone from the posterior pituitary.Hypothalamic or Central Diabetes insipidusA type of diabetes insipidus that occurs when the kidney is unable to respond to antidiuretic hormone.Nephrogenic diabetes insipidusTrue/False - Patients with suspected diabetes insipidus are usually assessed by a water deprivation test. Alternatively, a non-osmotic stimulus such as hypoglycaemia may be used to stimulate ADH secretion.TrueA test used in the differential diagnosis of polyuria, differentiating between cranial diabetes insipidus (CDI), nephrogenic diabetes insipidus (NDI) and primary polydipsia (compulsive water drinking).Water deprivation testThe most common pituitary disorder. Not life threatening but also not harmless.Pituitary tumorsTwo types of pituitary tumors.Secretory and Non-secretory tumorsTrue/False - Non-secretory tumors secrete too much of a hormone. While secretory tumors don't secrete excess hormone.False (opposite; secretory =secretes and non-secretory = don't secrete)Happens when pituitary function is suddenly disrupted (due to bleeding or trauma), creating a life-threatening shortage of vital hormones.Pituitary apoplexy