1. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.1 CHAPTER 18 ENDOCRINE SYSTEM

2. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.2 Chapter 18 Learning Objectives  Define 10 terms relating to the endocrine system.  Describe the function of the endocrine system.  Identify at least nine endocrine system structures.

3. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.3 Chapter 18 Learning Objectives  Identify at least one hormone produced by each of the 10 endocrine glands.  Describe at least three methods used to assess the function of the endocrine system.  Describe at least five disorders of the endocrine system.

4. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.4 Structure and Function of the Endrocrine System  Primary function of the endocrine system is to produce hormones that monitor and coordinate body activities.  Endocrine glands secrete hormones directly into the bloodstream.  Two classes of hormones  Nonsteroid First messengers First messengers  Steroid

5. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.5 The Endocrine System FIGURE 18-1 The endocrine system. (From Patton KT, Thibodeau GA: Anatomy & physiology, ed 7, St. Louis, 2010, Mosby.)

6. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.6 Hormones  Three categories of hormones  Tropic hormones Target other endocrine structures to increase growth and secretions Target other endocrine structures to increase growth and secretions  Sex hormones Influence reproductive changes Influence reproductive changes  Anabolic hormones Stimulate the process of building tissues Stimulate the process of building tissues

7. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.7 Hormones  Hormones direct many body processes, including  Growth  Metabolism  Reproduction  Hormones regulate the body’s reaction to stress and homeostasis.

8. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.8 Glands and Their Hormones  Hypothalamus  Located above the pituitary gland  Translates nervous system impulses into endocrine system messages  Regulates secretions of the pituitary adenohypophysis  Pituitary gland  Located at the base of the brain  Divided into two parts – anterior and posterior  Sometimes called the master gland Produces the hormones that regulate the secretion of other glands Produces the hormones that regulate the secretion of other glands

9. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.9 Glands and Their Hormones  Pineal body  Pea-shaped organ located in the brain  Produces the hormone melatonin Regulates the release of substances in the hypothalamus of the brain that influence secretion of sex hormones Regulates the release of substances in the hypothalamus of the brain that influence secretion of sex hormones Influences menstrual cycle and onset of puberty Influences menstrual cycle and onset of puberty Thought to be involved in the regulation of the biologic clock Thought to be involved in the regulation of the biologic clock

10. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.10 Glands and Their Hormones  Thyroid  Butterfly-shaped gland located in the neck  Produces hormones that regulate body metabolism: thyroxine and triiodothyronine Iodine is required for production of both. Iodine is required for production of both.  Produces calcitonin, which decreases the amount of calcium in the blood

11. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.11 Glands and Their Hormones  Parathyroid  Four tiny glands attached in the back of thyroid gland  Secretes parathyroid hormone, which affects the amount of calcium in the blood Increases the blood’s calcium level Increases the blood’s calcium level Increases the rate of phosphorus excretion by the kidneys Increases the rate of phosphorus excretion by the kidneys

12. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.12 Glands and Their Hormones  Thymus  Butterfly-shaped gland located above the heart  Produces thymosin Stimulates the lymphoid organs to produce T lymphocytes and antibodies in newborns or young children Stimulates the lymphoid organs to produce T lymphocytes and antibodies in newborns or young children

13. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.13 Glands and Their Hormones  Pancreas  Located behind the stomach  Produces the hormones insulin and glucagon Insulin regulates transportation of sugar, fatty acids, and amino acids into the cells. Insulin regulates transportation of sugar, fatty acids, and amino acids into the cells. Glucagon increases the blood sugar level. Glucagon increases the blood sugar level.  The pancreas is the only gland that has both endocrine and exocrine functions.

14. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.14 Glands and Their Hormones  Adrenals  Located above the kidneys  Divided into two layers Adrenal cortex Adrenal cortex  Produces about 30 hormones Adrenal medulla Adrenal medulla  Produces epinephrine (adrenalin) and norepinephrine –Epinephrine increases heart rate, blood pressure and blood sugar. Decreases blood flow to internal organs.

15. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.15 Glands and Their Hormones  Gonads  Primary sex glands Female: ovaries produce estrogen and progesterone Female: ovaries produce estrogen and progesterone  Hormones stimulate breast development, hair placement, and menstruation.  Estrogen initiates ovulation.  Progesterone assists in pregnancy. Male: testes produce hormone testosterone Male: testes produce hormone testosterone  Hormone stimulates secondary characteristics of the male.

16. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.16 Glands and Their Hormones  Prostaglandins  Fatty hormones produced by tissues  Can decrease blood pressure, cause fever, increase hydrochloric acid secretion in the stomach, increase uterine contraction during pregnancy, and influence intestinal peristalsis

17. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.17 Hormonal Changes of Puberty  Adrenal gland secretes the hormones that begin the development of secondary sexual characteristics.  In a man, the voice deepens, and facial hair begins to grow.  In a woman, the breasts enlarge, and fatty tissue is deposited around the hips.  In men and women, height and weight increase.

18. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.18 Hormonal Changes of Pregnancy  The placenta, or interfacing organ between the fetal and maternal circulation, produces a hormone called human chorionic gonadotropin (hCG).  Increased estrogen and progesterone from the ovaries are maintained until the placenta begins to produce these hormones.  Progesterone increases the mobility of the pelvic and lower back bones to allow the birthing process.  The pituitary and thyroid increase in size, resulting in a higher metabolic rate.

19. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.19 Hormonal Changes of Menopause  Menopause occurs after a decrease in secretion of the gonadotropins follicle- stimulating hormone (FSH) and luteinizing hormone (LH).  Ovarian secretion of the hormone estrogen is decreased.  Hot flashes, periods of feeling extreme heat, are the only universal symptom of menopause.

20. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.20 Assessment Techniques  Basal metabolic rate (BMR)  Amount of energy needed to maintain functions of resting body  Protein-bound iodine (PBI)  Blood test to measure the amounts of proteins attached to thyroxine  Immunoassay  Blood specimen is mixed with a specific chemical agent.  Number of complexes formed indicates the presence of certain hormones.

21. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.21 Assessment Techniques  Radioiodine uptake (RAIU) studies  Involves drinking radioactive iodine and measuring the iodine absorbed by the thyroid using a Geiger counter  Glucose tolerance testing (GTT)  Assesses function of pancreas using urine and blood specimens  Measures the efficiency of the insulin production of the pancreas

22. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.22 Disorders of the Endocrine System  Acromegaly  Enlargement of the bones of the hands, feet, and jaws  Addison's disease  Caused by hyposecretion of the hormones produced by the adrenal cortex  Cretinism  Condition resulting from a congenital deficiency of thyroid secretion or hypothyroidism

23. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.23 Disorders of the Endocrine System  Cushing’s syndrome  Disorder that causes hyperactivity of the adrenals  Triggered by the oversecretion of the pituitary hormone ACTH  Diabetes insipidus  Acquired or inherited decrease in the antidiuretic hormone secreted by the pituitary  Diabetes mellitus  Disorder of carbohydrate, fat, and protein metabolism resulting from insufficient insulin production by the pancreas

24. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.24 Signs and Symptoms of Diabetes Mellitus

25. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.25 Disorders of the Endocrine System  Dwarfism  Results from hyposecretion of growth hormone by the pituitary gland  May be caused by a tumor, infection, genetic factors, or trauma  Gigantism  Excessive growth of the long bones caused by hypersecretion of somatotropic hormone  Graves’ disease  Caused by hyperthyroidism or thyrotoxicosis

26. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.26 Disorders of the Endocrine System  Hyperparathyroidism  Causes hypercalcemia, an increased calcium blood level  Hypoglycemia  Results from increased insulin production by the pancreas  Hypoparathyroidism  Decreased secretion of parathyroid hormone, which causes tetany

27. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.27 Disorders of the Endocrine System  Hypothyroidism  Also called Hashimoto's disease, results from an insufficient production of thyroxine  Syndrome of inappropriate antidiuretic hormone (SIAH)  Involves water intoxication and the dilution of intracellular and extracellular body tissues, usually resulting from lung cancer  Virilism  Results from increased secretion in the adrenal glands

28. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.28 Issues and Innovations  Diabetes  About 8% of the population have diabetes Rates are highest in China, India, and the United States. Rates are highest in China, India, and the United States.  Exubera New form of insulin taken with an inhaler New form of insulin taken with an inhaler Can be used by type 1 and 2 diabetics Can be used by type 1 and 2 diabetics  Transplantation of a donor pancreas Used with various rates of success Used with various rates of success  Infusion of cord stem cell into children with type 1 diabetes Safe and may slow down progression of type 1 diabetes Safe and may slow down progression of type 1 diabetes

29. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.29 Issues and Innovations  Steroid abuse  Continues to be a problem, especially by athletes  Causes problems for men, such as stunted growth, liver tumors, and decreased sperm production  Causes problems for women, such as loss of menstrual cycle and baldness  Use of anabolic steroids may result in a prison sentence of up to 6 years.

30. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.30 Summary  The function of the endocrine system is to produce hormones that monitor and coordinate body activities.  Endocrine system structures  Pineal  Hypothalamus  Thyroid  Pituitary  Thymus glands  Others

31. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.31 Summary  The hormone produced by the thyroid gland (thyroxine) regulates body metabolism.  Methods used to assess the endocrine system  Basal metabolic rate  Protein-bound iodine blood tests  Radioactive uptake

32. Copyright © 2012, 2007, 2003, 1997, 1991 by Mosby, Inc., an affiliate of Elsevier Inc.32 Summary  Disorders of the endocrine system  Acromegaly  Cretinism  Cushing’s syndrome  Diabetes insipidus  Diabetes mellitus