Chapter 20 The Endocrine System

Hormones secreted by the anterior pituitary gland

Adrenocorticotropic hormone(ACTH)- stimulates adrenal cortex to produce cortisol, corticosteroids, and androgens; which are vital in metabolizing carbohydrates. Growth hormone (GH or hGH ) - stimulates growth and cell reproduction in all body tissues, it assists with movement of amino acids into tissue cells and transformation of amino acids into needed proteins, helps regulate blood nutrient level after eating and during fasting. Thyroid- stimulating hormone (TSH)- stimulates the thyroid gland to to produce and secrete thyroxine (T4) and T3. Follicle - stimulating hormone (FSH)- produced in gonadotropic cells, stimulates both the growth and secretion of ovarian follicles in women and the production of sperm in men. Luteinizing hormone (LH)- in women stimulates ovulation and the formation of the corpus luteum, which then produces progesterone, In men LH stimulates the production of sex hormones, including testosterone. Prolactin, lactogenic hormone (PRL)- stimulates breast development and milk production in women following pregnancy. (PRL also exist in males but its function is unknown. Lipotropin- influences lipolysis and steroidogenesis and stimulates melanocytes to produce melanin.

The nurse observes facial twitching and spasms of the hand when the blood pressure cuff is inflated on a client after surgical removal of the thyroid gland. What is the priority action by the nurse? a. administer a calcium supplement such as calcium gluconate as ordered. b. administer a glass of water with a tablespoon of salt by mouth. c. administer oral potassium chloride as ordered. d. administer a diuretic such as furosemide (Lasix) as ordered.

Answer A.

A client is taking oral glucocorticoids for the treatment of asthma. What finding by the nurse would be a significant concern? a. respiratory rate 22 b. a blood pressure of 140/60 mm Hg c. a heart rate of 92 d. a temperature of 100 degrees Fahrenheit

Answer D.

A client states to the nurse, "I feel cold all the of the time, have gained 20 lb, and I'm always tired." What laboratory studies will the nurse likely need to review? a. 24 hour catecholamine study b. T3 and T4 c. prolactin levels d. luteinizing hormone levels.

Answer: B T3 and T4

The nurse is obtaining objective data from a client taking long-term oral glucocorticoids. What findings obtained by the nurse correlate with glucocorticoid therapy? Select all that apply. a. round or "moon" face b. Hypoactive bowel sounds c. A large abdomen d. ridges on the fingernails e. "Buffalo" hump on back

Answer: a, c, e

A client has been prescribed a leukotriene inhibitor. What positive client outcome does the nurse monitor for? a. the client will have a decrease in fever. b. the client will not report chest pain. c. the client will have clear lung fields. d. the client will have active bowel sounds.

Answer: c

Describe four effects of aging on the endocrine system.

Decreased production of and receptivity to hormones at cellular level. Reproductive hormones decrease. Sexual tissue atrophies. Decrease in thyroid hormones. Decrease in pancreatic secretions.

Endocrine disorders in the elderly are not a result of: A: unregulated release of hormones B: inappropriete response to hormonal signals C: hypofunction or hyperfunction of a gland D: dysfunction of the hypothalamus E: increase in tiredness and lethargy

E. increase in tiredness and lethargy Endocrine disorders in the elderly are not a result of increase in tiredness and lethargy. They are a result of the hormonal changes that occur with aging such as unregulated release of hormones, inappropriate response to hormonal signals, hypofunction or hyperfunction of a gland, or dysfunction of the hypothalamus.

Differentiate between exocrine and endocrine glands. Exocrine

Exocrine- secrete special substances (hormones and/ or other materials) into ducts that open into the body's external or internal surfaces.

Is the following statement true or false? In type 1 diabetes, both insulin and amylin are produced in insufficient amounts.

False, In type 1 diabetes, both insulin and amylin are not secreted. In type 2 diabetes, both hormones are produced, but in insufficient amounts.

Is the following statement true or false? The luteinizing hormone plays the same role in males and females.

False, The luteinizing hormone helps control ovulation and menstruation; important in sustaining pregnancy in females. It stimulates Leydig cells to produce testosterone and stimulates secretion of androgens in males.

Describe the general functions of the endocrine system and the actions related to each.

Growth and maturation: regulates growth and maturation, regulates body's response to stress. Metabolism: regulates metabolism, regulates absorption of nutrients, regulates use of glucose in cellular respiration, maintains body ph by maintaining fluid and electrolyte concentrations. Reproduction: produces sexual characteristics, controls reproductive and birth processes, promotes normal growth and development, activates lactation, influences sexual response.

Describe the relationship between the hypothalamus and the pituitary gland.

Hypothalamus considered master controller or integrator, tiny but complex portion of the brain, attached to the pituitary glands by means of the infundibular stalk, specialized cells release hormones that either inhibit release, or promote release, of other hormones from the anterior lobe of pituitary.

Positive Feedback

If there is a need for a hormone to meet the body's needs, a message is carried to the appropriate gland

Hormones secreted by the middle pituitary gland

Melanocyte-stimulating hormone (MSH)- increases skin and hair pigmentation.

Discuss negative and positive feedback as they relate to the endocrine system

Negative: signals the controller (the specific gland) to correct a deviation from normal. After the desired effect is achieved, information is sent to the gland to halt secretion of the hormone.

Hormones secreted by the posterior pituitary gland

Oxytocin- stimulates the uterus to contract during delivery and helps to keep it contracted after delivery (to prevent hemorrhage). It also stimulates the release of milk from a mother's breasts and is involved in orgasm and circadian homeostasis. Vasopressin (antidiuretic hormone ADH)-It stimulates contraction of blood vessels to raise blood pressure; affects the uterus; and influences reabsorption of water by the kidney tubules.

Discuss the location of insulin secretion; explain how insulin and glucagon regulate blood sugar levels.

Pancreas is the location where insulin secretion happens. glucagon: raises blood sugar, and is needed to break down glycogen into glucose it also stimulates the breakdown of fats and proteins for conversion in the liver into additional glucose. Insulin: it lowers the blood sugar level. Beta cells secrete amylin, which response to food intake and works with insulin and glucagon to help regulate glucose balance.

Discuss the role of the thymus as an endocrine organ and its relationship to the body's immune response.

Produces thymosin, a protein that stimulates production of small lymphocytes called T cells. It secretes other hormones believed to assist in the maturation of T cells. T cells are essential for the development of cellular immunity and the body's response to invading organisms.

Endocrine glands

are located throughout the body, each contains a group of specialized cells that secrete hormones, (ductless glands, glands of internal secretion) secrete hormones directly into the bloodstream, where they are transported throughout the body.

Explain the role of prostaglandins.

are not hormones, but rather are hormone like- substances sharing characteristics with hormones and neurotransmitters. They can cause pain, perform a role in a platelet function, and stimulate either contraction or relaxation in smooth muscle. They influence blood pressure, respiration, digestion, reproduction, and inflammatory response.

Hormones

chemicals that regulate body processes, in response to body signals.

Briefly identify male and female sex hormones and functions of each.

gonads are the glands of reproduction: the male testes and female ovaries. the Leydig cells of the testes produce testosterone, the female ovaries produce estrogen and progesterone, which, in addition to regulating female sex characteristics, are responsible for mensuration; they also influence pregnancy, labor, and lactation.

Endocrinology

is the specialty that studies endocrine glands, their secretions, and related disorders.

Describe the functions of mineralocorticoids and glucocorticoids secreted by the adrenals.

mineralocorticoids: regulate the body's electrolytes. Aldosterone, the most important mineralocorticoids, stimulates reabsorption of sodium into plasma and secretion of potassium and hydrogen in the kidney, resulting in increased water reabsorption and, therefore, an increase in blood volume. glucocorticoids: have important influence on the synthesis of glucose, amino acids, and fats during metabolism. They also depress the immune response, decrease the inflammatory response, and contribute to the maintenance of normal blood pressure.

Describe the hormones involved in "Fight" or "Flight" give examples of their effects and body's responses during an emergency.

the medulla secretes catecholamines synthesized from amino acids. Examples: epinephrine and norepinephrine. epinephrine: important in managing and adapting to stress. It causes an increase in pulse rate, blood vessel contraction, a rise in BP, and increased muscle power, by causing the liver to release glucose for energy. norepinephrine: has some but not all actions of of epinephrine.

Describe the relationships between "releasing" hormones and "inhibiting" hormones.

their main purpose is to control the release of other hormones, either by stimulating or inhibiting their release.

Explain the functions of the thyroid hormones.

they regulate body metabolism, controlling the rate at which cells function.

Describe the actions of hormones responsible for calcium balance.

when the circulating calcium level is high, calcitonin responds by promoting increased storage of calcium in bones and increased renal excretion of calcium, resulting in lowered serum calcium. parathyroid hormone regulates the amounts of calcium in the blood so when blood calcium level is too low, PTH is secreted, increasing the number and size of osteoclasts therefore, PTH causes calcium to leave the bones and also enhances reabsorption of calcium and magnesium and excretion of phosphorus in the kidneys.