ENDOCRINE SYSTEM CHAPTER 13. Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 1

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1 ENDOCRINE SYSTEM CHAPTER 13 Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 1

2 Endocrine System Overview Endocrine System Consists of ductless glands Secrete hormones directly into bloodstream Affect the function of specific body organs Regulates many intricate body functions Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 2

3 Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 3

4 Pituitary Gland Pituitary Gland Referred to as the master gland Secretes hormones that control the functions of other glands Known as the hypophysis Has two distinct lobes with specific functions Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 4

5 Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 5

6 Pituitary Gland (continued) Anterior Pituitary Gland = Adenohypophysis Secretes Growth Hormone (GH) Also called Somatotropic Hormone (STH) Regulates growth of bone, muscle, and other body tissues Secretes Adrenocorticotropic Hormone (ACTH) Stimulates normal growth and development of adrenal cortex and secretion of corticosteroids Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 6

7 Pituitary Gland (continued) Anterior Pituitary Gland (continued) Secretes Thyroid-Stimulating Hormone (TSH) Promotes and maintains normal growth and development of the thyroid gland Stimulates secretions of the thyroid hormones Secretes Lactogenic Hormone (LTH) Also called Prolactin Promotes development of breasts during pregnancy Stimulates secretion of milk from breasts after delivery of baby Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 7

8 Pituitary Gland (continued) Anterior Pituitary Gland (continued) Secretes Follicle-Stimulating Hormone (FSH) Stimulates secretion of estrogen and production of eggs in the female ovaries Stimulates production of sperm in the male testes Secretes Luteinizing Hormone (LH) Stimulates female ovulation and the secretion of testosterone in the male Melanocyte-Stimulating Hormone (MSH) Controls the intensity of pigmentation in pigmented cells of the skin Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 8

9 Pituitary Gland (continued) Posterior Pituitary Gland = Neurohypophysis Secretes Antidiuretic Hormone (ADH) Decreases excretion of large amounts of urine from the body Increases reabsorption of water by the renal tubules Secretes Oxytocin (OT) Stimulates contraction of the uterus during childbirth Stimulates the release of milk from the breasts of lactating women in response to the suckling reflex of the infant Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 9

10 Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 10

11 Pineal Gland Pineal Gland Tiny, pine cone-shaped gland Located behind dorsal aspect of midbrain region Plays a part in supporting body s biological clock Regulation of patterns of eating, sleeping, and reproduction Secretes melatonin Induces sleep Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 11

12 Thyroid Gland Thyroid Gland Located in front of the neck just below the larynx, on either side of the trachea Consists of a right and left lobe Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 12

13 Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 13

14 Thyroid Gland (continued) Thyroid Gland (continued) Secretes Triiodothyronine (T3) Helps regulate growth and development of the body Helps control metabolism and body temperature Secretes Thyroxine (T4) Helps maintain normal body metabolism Secretes Calcitonin Helps regulate the level of calcium in the blood Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 14

15 Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 15

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17 Parathyroid Glands Parathyroid Glands Four tiny rounded bodies located on dorsal aspect of thyroid gland Secrete Parathyroid Hormone (PTH) Also known as parathormone Regulates level of calcium in the blood Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 17

18 Thymus Thymus Single gland located in the mediastinum near the middle of the chest, just beneath the sternum Large in fetus and infants, shrinks with age Secretes Thymosin and Thymopoietin Stimulates production of T cells that are involved in the immune response Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 18

19 Adrenal Glands Adrenal Glands Two small glands, one positioned atop each kidney Also known as the suprarenal glands Consists of an adrenal cortex and an adrenal medulla Each has independent functions Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 19

20 Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 20

21 Adrenal Glands (continued) Adrenal Cortex secretes Corticosteroids Mineralocorticoids Regulate how mineral salts (electrolytes) are processed in the body Glucocorticoids Influence metabolism of carbohydrates, fats, and proteins in the body Necessary for maintaining normal blood pressure Have an anti-inflammatory effect on the body Increase glucose available during fight-orflight responses by the body Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 21

22 Adrenal Glands (continued) Adrenal Cortex secretes (continued) Gonadocorticoids Sex hormones secreted in small amounts Contribute to secondary sex characteristics in males and females Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 22

23 Adrenal Glands (continued) Adrenal Medulla secretes Catecholamines Epinephrine = adrenaline Sympathiomimetic agent Increases heart rate and force of heart muscle contraction Dilates bronchioles in the lungs Decreases peristalsis in the intestines Raises blood glucose levels by causing the liver to convert glycogen into glucose Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 23

24 Adrenal Glands (continued) Adrenal Medulla secretes (continued) Norepinephrine = noradrenaline Known as a sympathomimetic agent Produces a vasoconstrictor effect on the blood vessels, thereby raising blood pressure Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 24

25 Pancreas Pancreas Elongated gland located in upper left quadrant of the abdomen, behind the stomach Extends horizontally across the body, beginning at the first part of the small intestines and ending at the edge of the spleen Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 25

26 Pancreas (continued) Islets of Langerhans secrete Glucagon Increases blood glucose levels by stimulating liver to convert glycogen into glucose when blood sugar is extremely low Insulin Makes it possible for glucose to pass from blood through cell membranes to be used for energy Promotes conversion of excess glucose into glycogen for storage in the liver for later use Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 26

27 Ovaries Ovaries Female sex glands = female gonads Pair of almond shaped glands Located in upper pelvic cavity, on either side of lateral wall of uterus Near fimbriated ends of the fallopian tubes Responsible for producing mature ova and releasing them at monthly intervals during ovulation Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 27

28 Ovaries (continued) Hormones secreted by the Ovaries Estrogen Promotes the maturation of the ovum in the ovary Stimulates vascularization of the uterine lining each month in preparation for implantation of a fertilized egg Contributes to secondary sex characteristic changes in the female with onset of puberty Progesterone Primarily responsible for changes that occur within the uterus in anticipation of a fertilized ovum Responsible for development of the maternal placenta after implantation of a fertilized ovum Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 28

29 Testes Testes = male gonads = testicles Two small ovoid glands located in the scrotum Primary organs of the male reproductive system Responsible for production of sperm and secretion of androgens (male steroid hormones) Secrete Testosterone Responsible for secondary sex characteristic changes that occur in the male with onset of puberty Responsible for maturation of sperm Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 29

30 PATHOLOGICAL CONDITIONS of the PITUITARY GLAND Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 30

31 Acromegaly Pronounced (ak-roh-meg-ah-lee) Defined Chronic metabolic condition characterized by the gradual, noticeable enlargement and elongation of the bones of the face, jaw, and extremities, due to hypersecretion of the human growth hormone after puberty Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 31

32 Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 32

33 Diabetes Insipidus Pronounced (dye-ah-bee-teez in-sip-ih-dus) Defined A condition caused by a deficiency in the secretion of antidiuretic hormone (ADH) by the posterior pituitary gland Characterized by large amounts of urine and sodium being excreted from the body Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 33

34 Dwarfism Pronounced (DWARF-ism) Defined Generalized growth retardation of the body due to the deficiency of the human growth hormone Also known as congenital hypopituitarism or hypopituitarism Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 34

35 Gigantism Pronounced (JYE-gan-tizm) Defined A proportional overgrowth of the body s tissue due to the hypersecretion of the human growth hormone before puberty Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 35

36 Hypopituitarism Pronounced (high-poh-pih-too-ih-tah-rizm) Defined Complex syndrome resulting from the absence or deficiency of the pituitary hormone(s) Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 36

37 PATHOLOGICAL CONDITIONS of the THYROID GLAND Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 37

38 Cancer, Thyroid Gland Pronounced (CAN-sir, THIGH-royd gland) Defined Malignant tumor of the thyroid gland, which leads to dysfunction of the gland and thus inadequate or excessive secretion of the thyroid hormone Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 38

39 Goiter, Simple; Nontoxic Pronounced (GOY-ter Simple; Nontoxic) Defined Hyperplasia of the thyroid gland Results from a deficient amount of iodine in the diet, required for synthesis of T3 and T4, thyroid hormones produced by the thyroid gland Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 39

40 Graves Disease (Hyperthyroidism) Pronounced (high-per-thigh-royd-izm) Defined Hypertrophy of the thyroid gland resulting in an excessive secretion of the thyroid hormone Causes an extremely high body metabolism, thus creating multisystem changes Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 40

41 Graves Disease Hyperthyroidism (continued) Three Distinguishing Characteristics Hyperthyroidism Thyroid gland enlargement (goiter) Exophthalmia Unnatural protruding of the eyes Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 41

42 Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 42

43 Hypothyroidism Pronounced (high-poh-thigh-royd-izm) Defined Condition in which there is a shortage of thyroid hormone causing an extremely low body metabolism due to a reduced usage of oxygen Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 43

44 Hypothyroidism (continued) Hypothyroidism (continued) Most severe form known as myxedema Water retention all over body in connective tissues Person has puffy appearance and thick tongue Reduced metabolic rate Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 44

45 Thyroiditis (Hashimoto s) Pronounced (thigh-royd-eye-tis) (HASH-ee-moh-TOZ) Defined Chronic inflammation of the thyroid gland, leading to enlargement of the thyroid gland Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 45

46 Thyrotoxicosis (Thyroid Storm) Pronounced (thigh-roh-toks-ih-koh-sis) Defined An acute, sometimes fatal, incident of overactivity of the thyroid gland resulting in excessive secretion of thyroid hormone Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 46

47 PATHOLOGICAL CONDITIONS of the PARATHYROID GLAND Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 47

48 Hyperparathyroidism (Hypercalcemia) Pronounced (high-per-pair-ah-thigh-royd-izm) (high-per-kal-see-mee-ah) Defined Overactivity of any one of the parathyroid glands, which leads to high levels of calcium in the blood and low levels of calcium in the bones Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 48

49 Hypoparathyroidism Pronounced (high-poh-pair-ah-thigh-royd-izm) Defined Decreased production of parathyroid hormone resulting in hypocalcemia, characterized by nerve and muscle weakness with muscle spasms or tetany Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 49

50 Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 50

51 PATHOLOGICAL CONDITIONS of the ADRENAL GLANDS Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 51

52 Addison s Disease Pronounced (AD-ih-sons dih-zeez) Defined A life-threatening disease process due to failure of the adrenal cortex to secrete adequate mineralocorticoids and glucocorticoids Resulting from an autoimmune process, a neoplasm, an infection, or a hemorrhage in the gland Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 52

53 Conn s Disease (Primary Aldosteronism) Pronounced (PRYE-mary al-doss-stair-ohn-izm) Defined Condition characterized by excretion of excessive amounts of aldosterone Leads to an increased volume of blood and hypertension Causes the body to retain extra sodium and excrete extra potassium Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 53

54 Cushing s Syndrome Pronounced (CUSH-ings SIN-drom) Defined Condition of the adrenal gland in which there is a cluster of symptoms occurring as a result of an excessive amount of cortisol or ACTH circulating in the blood Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 54

55 Cushing s Syndrome (continued) Cushing s Syndrome Symptoms Central obesity Round moon face Edema Hypertension Supraclavicular fat pads (buffalo hump) Muscular weakness and wasting Skin infection Poor wound healing Low potassium level Emotional changes Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 55

56 Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 56

57 Pheochromocytoma Pronounced (fee-oh-kroh-moh-sigh-toh-mah) Defined Vascular tumor of the adrenal medulla that produces extra epinephrine and norepinephrine, leading to persistent or intermittent hypertension and heart palpitations Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 57

58 Virilism Pronounced (VEER-il-izm) Defined Development of male secondary sex characteristics in the female due to the excessive secretion of adrenocortical androgens from the adrenal cortex Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 58

59 Virilism (continued) Virilism Symptoms Excessive hair on the body and face (hirsutism) Absence of menstruation Deepening of the voice Acne Oily skin Muscular hypertrophy Atrophy of the breasts and uterus Ovarian changes Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 59

60 PATHOLOGICAL CONDITIONS of the PANCREAS Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 60

61 Diabetes Mellitus Pronounced (dye-ah-bee-teez MELL-ih-tus) Defined A disorder of the pancreas in which the beta cells of the islets of Langerhans of the pancreas fail to produce an adequate amount of insulin Results in the body s inability to appropriately metabolize carbohydrates, fats, and proteins Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 61

62 Diabetes Mellitus (continued) Classifications Insulin-Dependent Diabetes Mellitus (IDDM) Also known as Type I diabetes Usually occurs before the age of 30 Sudden onset Controlled with insulin injections Individuals are prone to developing ketosis Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 62

63 Diabetes Mellitus (continued) Classifications (continued) Non-Insulin-Dependent Diabetes Mellitus (NIDDM) Also known as Type II diabetes Usually appears in adults after the age of 40 Majority of these individuals are obese Usually controlled through diet and exercise Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 63

64 Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 64

65 Pronunciation Diabetic Retinopathy (dye-ah-bet-ik ret-in-op-ah-thee) Defined A disorder of the blood vessels of the retina of the eye in which the capillaries of the retina experience localized areas of bulging (microaneurysms), hemorrhages, and scarring Consequence of an 8-10 year duration of diabetes mellitus Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 65

66 Gestational Diabetes Pronounced (jess-tay-shun-al dye-ah-bee-teez) Defined A disorder in which women who are not diabetic before pregnancy develop diabetes during the pregnancy They develop an inability to metabolize carbohydrates, with resultant hyperglycemia Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 66

67 Pancreatic Cancer Pronounced (pan-kree-at-ik CAN-sir) Defined A life-threatening primary malignant neoplasm typically found in the head of the pancreas Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 67

68 Pancreatitis Pronounced (pan-kree-ah-tye-tis) Defined An acute or chronic destructive inflammatory condition of the pancreas Acute pancreatitis creates symptoms that vary from mild self-limiting pancreatic edema to massive necrotizing hemorrhagic pancreatitis Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 68

69 Diagnostic Techniques and Procedures Thyroid Function Tests Tests that measure the blood levels of the hormones T3, T4, and TSH Thyroid-Stimulating Hormone (TSH) Blood Test A test that measures the concentration of TSH in the blood Used to differentiate primary hypothyroidism from secondary hypothyroidism Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 69

70 Diagnostic Techniques and Procedures (continued) Fasting Blood Sugar (FBS) Blood glucose sample taken usually early in the morning after the person has been without food or drink since midnight Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 70

71 Diagnostic Techniques and Procedures (continued) Glucose Tolerance Test (GTT) A test that evaluates the person s ability to tolerate a concentrated oral glucose load by measuring the glucose levels: Prior to glucose administration 30 minutes after glucose administration 1,2,and 3 hours after glucose administration Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 71

72 Diagnostic Techniques and Procedures (continued) Radioactive Iodine Uptake (RAIU) Test A thyroid function test that evaluates the function of the thyroid gland by administering a known amount of radioactive iodine and later placing a gamma ray detector over the thyroid gland to determine the percentage or quantity of radioactive iodine absorbed by the gland over specific time periods Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 72

73 Diagnostic Techniques and Procedures (continued) Serum Glucose Tests Tests that measure the amount of glucose in the blood at the time the sample was drawn Thyroid Echogram (Ultrasound) An ultrasound examination important in distinguishing solid thyroid nodules from cystic nodules Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 73

74 Diagnostic Techniques and Procedures (continued) Thyroid Scan An examination that determines the position, size, shape, and physiological function of the thyroid gland through the use of radionuclear scanning Copyright 2003 by Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED 74