This document contains lecture slides about the endocrine system from a textbook on anatomy and physiology. It includes information on the major endocrine glands like the pituitary gland, thyroid gland, parathyroid gland, adrenal glands, pancreas and the hormones they secrete. It also discusses the functions of hormones, types of hormones, and feedback mechanisms that regulate hormone secretion. Key endocrine concepts like the hypothalamus-pituitary axis and control of calcium levels are explained through diagrams and figures.

1. Seeley’s
ESSENTIALS OF
Anatomy &
Physiology
Tenth Edition
Cinnamon Vanputte
Jennifer Regan
Andrew Russo
See separate PowerPoint slides for all figures and tables
pre-inserted into PowerPoint without notes.
© 2019 McGraw-Hill Education. All rights reserved. Authorized only for instructor use in the classroom. No reproduction or further distribution permitted without the prior written consent of McGraw-Hill Education.

2. © 2019 McGraw-Hill Education
2
Chapter 10
Endocrine System
Lecture Outline

3. © 2019 McGraw-Hill Education
3
SCENARIO: Katie was getting nervous. At 16,
she was the only one in her group of friends
who had not started menstruating. Katie has
always dreamed of having three beautiful
children and she was worried. Her mother took
her to see Dr. Josephine, who ordered several
blood test. When the results came back, Dr.
Josephine gently explained to Katie and her
mother that Katie would never be able to have
children and would never menstruate. Dr.
Josephine then asked Katie to wait in the outer
room while she spoke privately to her mother.

4. © 2019 McGraw-Hill Education
4
She explained to Katie’s mom that Katie had
Androgen Insensivity Syndrome. Though Katie
was genetically male and her gonads produce
more of the male reproductive hormone,
testosterone, than the female reproductive
hormone female, estrogen.

5. © 2019 McGraw-Hill Education
5
Endocrine System Glands
Figure 10.1

6. © 2019 McGraw-Hill Education
6
Chemical Messengers
 Are hormones that allows the cells to
communicate with each other to regulate
body activities.
 Four classes: Autocrine, Paracrine,
Neurotransmitter, and Endocrine
 Endocrine chemical messengers are
called HORMONES

7. © 2019 McGraw-Hill Education
7
Cell Secretion Types1
Autocrine
 Secreted by cells in local effect area and influences
the activity of the same cell.
 Example - eicosanoids
Paracrine
 Produced by a wide variety of tissues and secreted
in ECF
 Example – somatostatin, histamine

8. © 2019 McGraw-Hill Education
8
Cell Secretion Types
Neurotransmitter
 produced by neuron, secreted in the synaptic cleft
that activate adjacent cell
 Example - Acethycholine
Endocrine
 secreted into blood and bind to receptor sites
 Example - epinephrine and insulin, estrogen, GH,
testosterone, and estrogen

9. © 2019 McGraw-Hill Education
9
Endocrine System Functions1
 Metabolism
 Control of food intake and
digestion
 Tissue development
 Ion regulation
 Water balance

10. © 2019 McGraw-Hill Education
10
Endocrine System Functions2
 Heart rate and blood pressure
regulation
 Control of blood glucose and
other nutrients
 Control of Reproductive
functions
 Uterine contraction and milk
release
 Immune System regulation

11. © 2019 McGraw-Hill Education
11
Endocrine System
 composed of endocrine glands and
specialized endocrine cells located
throughout the body.
 Endocrine glands and cells secretes
chemical messengers called hormones
into the bloodstream or blood circulation
to target tissues or effectors.

12. © 2019 McGraw-Hill Education
12
Types of Hormones
Water-soluble hormones:
 includes proteins, peptides, amino acids
 most common, can dissolve in blood
 Examples - growth hormone, antidiuretic, prolactin
Lipid-soluble hormones:
 includes steroids and eicosanoids
 Examples - LH, FSH, androgens

13. © 2019 McGraw-Hill Education
13
Regulation of Hormone Levels
Negative Feedback mechanism
 the hormone’s secretion is inhibited by the
hormone itself once blood levels have reached a
certain point.
Positive Feedback mechanism
 hormones are regulated as exemplified by tropic
hormone action.
 The response to the stimulus does not stop
or reverse the stimulus, but instead keeps the
sequence of event going.

14. © 2019 McGraw-Hill Education
14
Negative and Positive Feedback
Figure 10.5

15. © 2019 McGraw-Hill Education
15
Classification of HORMONES
1. AMINES
 Structural variations of the amino acids
 tyrosine, thyroxine and epinephrine
norepinephrine.
2. PROTEINS
 Are chains of amino acids
 Insulin, growth hormones, and calcitonin.

16. © 2019 McGraw-Hill Education
16
STEROIDS
 Includes cortisol, and aldosterone, estrogen
and progesterone, and testosterone.

17. © 2019 McGraw-Hill Education
17
HYPOTHALAMUS
 superior to the pituitary gland and
inferior to the thalamus
 regulates the secretions of hormones of
the pituitary gland

18. © 2019 McGraw-Hill Education
18
Pituitary Gland
 Small gland in brain
 Controlled by hypothalamus
 Divided into 2 regions:
Anterior and Posterior
 Secretes at least 8 hormones

19. © 2019 McGraw-Hill Education
19
Pituitary Gland2
Figure 10.12

20. © 2019 McGraw-Hill Education
20
Anterior Pituitary Hormones1
Growth Hormone
 Target tissues: most
 stimulates growth of bones, muscles, and
organs
 Stimulate cells to produce insulin like growth
factors
 Increase the rate of CHON synthesis
 increases the use of fats as energy
metabolism.

21. © 2019 McGraw-Hill Education
21
Growth Hormone
 It increases blood glucose levels by reducing
glucose utilization (insulin antagonist)
 Abnormalities
 Too much GH causes giantism
 Too little GH causes pituitary dwarfism

22. © 2019 McGraw-Hill Education
22
Anterior Pituitary Hormones5
Prolactin
 AKA mammotropic hormone, lactotropic
hormone
 Target tissues: mammary glands and
ovaries
 Functions: milk production
 It is necessary for breast development and
lactation

23. © 2019 McGraw-Hill Education
23
 Prolactin Releasing Hormone (PRH)
stimulate the secretion from the
hypothalamus.
 Prolactin Inhibiting Hormone inhibits
the secretion from the hypothalamus

24. © 2019 McGraw-Hill Education
24
Anterior Pituitary Hormones
Thyroid-Stimulating Hormone
(TSH)
• AKA thyrotropin
• Target tissues: thyroid gland
• Functions: regulates thyroid gland secretions
• Thyroxine (T4) and thriodothyronine T3 by the TG
• Thyrotropin releasing hormone - triggers the
pituitary gland to release TSH.

25. © 2019 McGraw-Hill Education
25
• Abnormalities:
Too much TSH, thyroid gland enlarges
Too little TSH, thyroid gland shrinks

26. © 2019 McGraw-Hill Education
26
Regulation of Thyroid Hormone
Secretion
Figure 10.16

27. © 2019 McGraw-Hill Education
27
Gonadotrophin Hormone
LH (Luteinizing) for females
 Target tissue: ovaries
 Function: promotes ovulation and progesterone
production
LH for males
 Target tissue: testes
 Function: sperm production and testosterone

28. © 2019 McGraw-Hill Education
28
Anterior Pituitary Hormones4
Gonadotrophin Hormone
Follicle-Stimulating for females
• Target tissue: follicles in ovaries
• Function: follicle maturation and estrogen secretion
FSH for males
• Target tissue: seminiferous tubules (testes)
• Function: sperm production

29. © 2019 McGraw-Hill Education
29
Anterior Pituitary Hormones6
Melanocyte Stimulating Hormone (MSH)
 Target tissues: melanocytes in the skin
 Functions: stimulate melanin production in
melanocytes to make skin darker
Adrenocorticotrophic Hormone (ACTH):
 Target tissues: cells of adrenal cortex
 Functions: stimulate production of certain
corticosteroids,

30. © 2019 McGraw-Hill Education
30
ANTERIOR PITUITARY GLAND
1. Growth Hormone
2. Thyroid-Stimulating Hormone (TSH)
3. Gonadotrophin Hormone
 LH
 FSH
4. Prolactin
5. Melanocyte Stimulating Hormone
6. Adrenocorticotrophic Hormone
(ACTH):

31. © 2019 McGraw-Hill Education
31
Posterior Pituitary
 synthesizes and releases
hormones produced by
neuroendocrine cells in the
hypothalamus.
 Antidiuretic hormone (ADH) and
Oxytocin.

32. © 2019 McGraw-Hill Education
32
PPG Hormones
1. Antidiuretic Hormone (ADH)
 AKA VASOPRESSIN
 Target tissues: KIDNEYS
 Functions:
 conserve water, decreases sweating, urinary
output is decrease
 VASOCONSTRICTION in arterioles to raise or
maintain BP

33. © 2019 McGraw-Hill Education
33
 Abnormalities: Diabetes Insipidus
• Low ADH production
• kidneys produce large amounts of dilute
• (watery) urine
• can lead to dehydration and thirst

34. © 2019 McGraw-Hill Education
34
Posterior Gland Hormones2
Oxytocin
• Target tissues: Uterus
• Cause contraction of myometrium of
the uterus during labor has begun.
• Stimulus: nerve impulses from the
hypothalamus as cervix is stretched and
as infants suck the nipple

35. © 2019 McGraw-Hill Education
35
Hypothalamus and Posterior Pituitary
Figure 10.14

36. © 2019 McGraw-Hill Education
36
Thyroid Gland
 One of largest glands
 located in front and on the side of the trachea just
below the larynx.
 Requires iodine to function
 Secretes Thyroid hormone and Calcitonin

37. © 2019 McGraw-Hill Education
37
Thyroid hormones
 secreted by follicular cells
 produces T3 and T4
 Target tissues: most
 regulates metabolic rates and is needed for
growth
 Regulate CHON, CHO and fat metabolism
 Necessary for normal physical, mental and
sexual development.
 Act as insulin antagonist

38. © 2019 McGraw-Hill Education
38
Calcitonin
 secreted or produced by parafollicular cells
 Target tissues: bone and some other tissues
 reduces blood calcium level when high
 It inhibits osteoclastic activity
 It lowers phosphate levels
 It helps maintain stable and strong bones matrix.
 High Calcitonin- Low Calcium
 Low Calcitonin- High Calcium

39. © 2019 McGraw-Hill Education
39
Thyroid Hormone Disorders
Hypothyroidism:
• Decreased metabolism
• Weight gain, reduced
appetite, fatigue
• Low temp. and pulse
• Dry, cold skin
• Myxedema in adults
• Cretinism in infants
Hyperthyroidism:
• Increased metabolism
• Weight loss, increased
appetite, nervousness
• Higher temp. and pulse
• Warm, flushed skin
• Graves’ disease (leads
to goiter)

40. © 2019 McGraw-Hill Education
40
Parathyroid Gland
Parathyroid hormone (PTH)
 Target tissues: bones and kidneys
 Functions: regulates blood Ca2+ levels (more
than calcitonin)
 If Ca 2+ is low then osteoclasts break down bone
matrix and less Ca 2+ is lost in urine.
 If Ca 2+ is high then osteoclasts don’t break down
bone matrix and more Ca 2+ is lost in urine.

41. © 2019 McGraw-Hill Education
41
Regulation of Blood Calcium Levels
Figure 10.17

42. © 2019 McGraw-Hill Education
42
Thyroid Gland and Parathyroid Glands
Figure 10.15
(d) ©Victor Eroschenko

43. © 2019 McGraw-Hill Education
43
Adrenal Glands
 two small glands located superior to each
kidney
 Each adrenal gland has an inner part, called
the adrenal medulla, and an outer part, called
the adrenal cortex.
 The adrenal medulla and the adrenal cortex
function as separate endocrine glands.

44. © 2019 McGraw-Hill Education
44
Adrenal Glands
Figure 10.18
(c) ©Victor Eroschenko

45. © 2019 McGraw-Hill Education
45
Adrenal Gland Hormones1
Adrenal medulla hormones:
• Epinephrine/Norepinephrine:
• Target tissues: heart, blood vessels, liver, fat cells
• Functions: released as part of fight or flight response

46. © 2019 McGraw-Hill Education
46
Regulation of Adrenal Medullary
Secretions
Figure 10.19

47. © 2019 McGraw-Hill Education
47
Adrenal Gland Hormones2
Adrenal cortex hormone
Aldosterone
Type of mineralocorticoids
Target tissues: kidneys
Causes Na+ and H2O to be retained
and K+ to be secreted,
indirectly involved with blood pressure
and blood volume

48. © 2019 McGraw-Hill Education
48
Regulation of Aldosterone Secretion
Figure 10.20

49. © 2019 McGraw-Hill Education
49
Adrenal Gland Hormones3
Cortisol:
• Type of glucocorticoids
• Target tissues: most
• Functions: increases breakdown of fat and
• protein for energy uses reduces inflammatory and
immune responses

50. © 2019 McGraw-Hill Education
50
Regulation of Cortisol Secretion
Figure 10.21

51. © 2019 McGraw-Hill Education
51
Adrenal Gland Hormones4
Androgens:
• Target tissues: most
• Functions:
• Males: secondary sexual characteristics
• Females: sex drive

52. © 2019 McGraw-Hill Education
52
Pancreas
 is a mixed gland, with an exocrine portion and
an endocrine portion.
 The exocrine portion of the pancreas secretes
digestive enzymes.
 The endocrine part of the pancreas consists of
pancreatic islets (islets of Langerhans), which
are dispersed throughout the exocrine portion
of the pancreas.

53. © 2019 McGraw-Hill Education
53
Pancreas
 The islets consist of three cell types, each of
which secretes a separate hormone.
 Alpha cells secrete glucagon,
 Beta cells secrete insulin,
 Delta cells secrete somatostatin.
 These three hormones regulate the blood
levels of nutrients, especially glucose

54. © 2019 McGraw-Hill Education
54
Pancreas Structure
Figure 10.22
©Biophoto Associates/Science Source

55. © 2019 McGraw-Hill Education
55
Pancreas Hormones1
Insulin
• Target tissues: liver, skeletal muscle, adipose
tissue
• Functions
• regulates blood glucose levels
• after a meal glucose levels are high and
insulin is secreted
• extra glucose is stored in form of glycogen

56. © 2019 McGraw-Hill Education
56
Insulin Abnormalities
Diabetes mellitus:
• Causes: too little insulin or faulty insulin receptors
• Symptoms: exaggerated appetite, excess urine,
dehydration, thirst, fatigue
• Type I: insulin dependent (daily injections required)
• Type II: insulin independent, often found in obese
people, can be treated with diet but can turn into
type I

57. © 2019 McGraw-Hill Education
57
Pancreas Hormones2
Glucagon
• Target tissues: liver
• Function:
• regulates blood glucose levels
• between meals glucose levels drop and
glucagon is secreted
• glucagon allows glycogen to be broken down
into glucose

58. © 2019 McGraw-Hill Education
58
Regulation of Blood Glucose Levels
Figure 10.23

59. © 2019 McGraw-Hill Education
59
Testes Hormone
Testosterone
• Target tissues: most
• Functions:
 Produced by interstitial cells
 Promotes maturation of sperm
 Stimulates the development of secondary sex
characteristics
 Promotes the closure of epiphysis of long bones

60. © 2019 McGraw-Hill Education
60
Ovarian Hormones
Estrogen/Progesterone:
• Target tissues: most
• Functions: involved in uterine and mammary gland
development and menstrual cycle

61. © 2019 McGraw-Hill Education
61
Thymus Gland Hormone
Thymosin:
• Target tissues: immune system tissues
• Functions: promotes immune system development
and function

62. © 2019 McGraw-Hill Education
62
Pineal Gland Hormone
Melatonin:
Target tissues: hypothalamus
Functions:
 plays a role in onset of puberty and
 controls circadian rhythms.
 Light affects its function.