1. CHAPTER 18 ENDOCRINE SYSTEM
Immunoassay Endocrine
Polydipsia
Polyphagia
Polyuria
Prostaglandin
Puberty
Basal metabolic rate
Endocrine
Exophthalmos
Gonadotropin
Hormone
Hyperglycemia
Hypoglycemia
Journal question: What is the primary function of the endocrine system.

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. 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. 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
Steroid
How does the endocrine system help to maintain the body’s homeostasis?

5. The Endocrine System
FIGURE 18-1 The endocrine system. (From Patton KT, Thibodeau GA: Anatomy & physiology, ed 7, St. Louis, 2010, Mosby.)

6. Hormones Three categories of hormones Tropic hormones Sex hormones
Target other endocrine structures to increase growth and secretions
Sex hormones
Influence reproductive changes
Anabolic hormones
Stimulate the process of building tissues

7. Hormones Hormones direct many body processes, including
Growth
Metabolism
Reproduction
Hormones regulate the body’s reaction to stress and homeostasis.
How do hormones regulate the body’s reaction to stress?

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
What does the prefix hypo mean?
Why is the pituitary gland called the master gland?

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
Influences menstrual cycle and onset of puberty
Thought to be involved in the regulation of the biologic clock
Discuss the term biologic clock and how it is affected by the hormone melatonin.

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.
Produces calcitonin, which decreases the amount of calcium in the blood

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 rate of phosphorus excretion by the kidneys
Why is it important to regulate the blood’s calcium level?

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

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.
Glucagon increases the blood sugar level.
The pancreas is the only gland that has both endocrine and exocrine functions.
Explain how the pancreas has both endocrine and exocrine functions.

14. Glands and Their Hormones
Adrenals
Located above the kidneys
Divided into two layers
Adrenal cortex
Produces about 30 hormones
Adrenal medulla
Produces epinephrine (adrenalin) and norepinephrine
Epinephrine increases heart rate, blood pressure and blood sugar. Decreases blood flow to internal organs.
Discuss the hormone epinephrine and the fight or flight reaction to stress.

15. Glands and Their Hormones
Gonads
Primary sex glands
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
Hormone stimulates secondary characteristics of the male.
Discuss the secondary characteristics of the male.

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. 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.
Discuss the term secondary sexual characteristics.

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. 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. 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.
Basil metabolic rate is measured by a test called indirect calorimetry, which measures the amount of oxygen consumed.
Protein-bound iodine assessment results can be influenced by cough syrups, iodine used in tests, diuretics, steroids, and pregnancy.

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
Ask the class if any student has taken a glucose tolerance test. Have the student tell about their experience in taking the test.

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
Discuss the causes, symptoms, and treatment for these disorders.

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
Discuss the causes, symptoms, and treatment for these disorders.

24. Signs and Symptoms of Diabetes Mellitus

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. 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
Discuss the term “tetany”.

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
Discuss the causes, symptoms, and treatment for these disorders.

28. Issues and Innovations
Diabetes
About 8% of the population have diabetes
Rates are highest in China, India, and the United States.
Exubera
New form of insulin taken with an inhaler
Can be used by type 1 and 2 diabetics
Transplantation of a donor pancreas
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
Ask the class their thoughts on why these three countries have the highest populations with diabetes.

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.
Initiate a discussion on recent articles about athletes abusing steroids. Why do they think there is such a need for athletes to abuse steroid use?

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. 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. Summary Disorders of the endocrine system Acromegaly Cretinism
Cushing’s syndrome
Diabetes insipidus
Diabetes mellitus

33. Review Adenoma, with regard to the endocrine system, is:
a. Inflammation of the pancreas
b. A tumor of a gland
c. Excessive excretion of urine
d. Enlargement of the extremities
e. Softening of a gland

34. Review Adenoma, with regard to the endocrine system, is:
a. Inflammation of the pancreas
b. A tumor of a gland
c. Excessive excretion of urine
d. Enlargement of the extremities
e. Softening of a gland

35. Review Addison’s disease is:
a. A disorder resulting from an acquired or inherited decrease in antidiuretic hormone secreted by the pituitary
b. A disorder that causes hyperactivity of the adrenal glands
c. A condition resulting from a congenital deficiency of thyroid secretion
d. A complex disorder of carbohydrate, fat, and protein metabolism
e. Caused by hyposecretion of the hormones produced by the cortex of the adrenal gland

36. Review Addison’s disease is:
a. A disorder resulting from an acquired or inherited decrease in antidiuretic hormone secreted by the pituitary
b. A disorder that causes hyperactivity of the adrenal glands
c. A condition resulting from a congenital deficiency of thyroid secretion
d. A complex disorder of carbohydrate, fat, and protein metabolism
e. Caused by hyposecretion of the hormones produced by the cortex of the adrenal gland