1. Endocrine Physiology
โดย
นางสาวพัชฎา บุตรยะถาวร
ครู ผ้สอน
ู
โรงเรียนเตรีมอุดมศึกษาน้ อมเกล้ า ปทุมธานี

2. Endocrine vs. Nervous System
• Major communication systems in the body
• Integrate stimuli and responses to changes
in external and internal environment
• Both are crucial to coordinated functions of
highly differentiated cells, tissues and
organs
• Unlike the nervous system, the endocrine
system is anatomically discontinuous.

3. Introduction
• The endocrine system includes the organs of the body
that secrete hormones directly into body fluids such
as blood
– Regulates chemical reaction in cells and therefore control
functions of the organs, tissues, and other cells
bloodstream
to
Glands
into
secrete
hormones
34-3
target tissues

4. Hormones
• Endocrine glands
– Ductless
– Release hormones
• Directly into target tissues
• Into bloodstream to be carried to target tissues
• Hormones – chemicals secreted by a cell
that affect the functions of other cells
34-4

5. Hormones (cont.)
• Many are derived from steroids that easily
cross the cell membrane
• Examples of steroid hormones
–
–
–
–
Estrogen
Progesterone
Testosterone
Cortisol
hormones
34-5

6. Hormones (cont.)
• Nonsteroidal hormones
• Prostaglandins
– Made of amino acids or
proteins and cannot cross the
cell membrane easily
– Local, or tissue, hormones
– Derived from lipid molecules
– Do not travel in the
bloodstream
– Target tissues are located close
by
– Produced by organs such as
– Bind to receptors on the
surface of the cells
– G-protein – activated by the
hormone-receptor complex
•
•
•
•
•
• Activates enzymes inside cell
34-6
Kidneys
Heart
Stomach
Uterus
Brain

7. Negative and Positive
Feedback Loops
• Control hormone levels
• Negative feedback loop
– Hormone release stops in response to decrease
in stimulus
• Stimulus (eating) raises blood glucose levels
• Pancreas releases insulin in response to elevated
blood glucose
• Blood glucose decreases as it is used by the body or
stored in the liver
• Insulin release stops as blood glucose levels
normalize
34-7

8. Negative and Positive
Feedback Loops (cont.)
• Positive feedback loop
– As long as stimulus is present, action of
hormone continues
• Infant nursing at mother’s breast  stimulates
hypothalamus  stimulates posterior pituitary
• Oxytocin released  stimulates milk production and
ejection from mammary glands
• Milk release continues as long as infant continues to
nurse
34-8

9. Apply Your Knowledge
Match the following:
ANSWER:
___ Chemicals that effect cell function A. Nonsteroidal hormone
E
B
___ Easily cross cell membranes
B. Steroidal hormone
A
___ Made of amino acids
C. G-protein
D
___ Target nearby cells
D. Prostaglandins
___ Activated by hormone-receptor
C
complex
E. Hormones
___ Cannot cross cell membranes easily
A
B
___ Estrogen and cortisol
34-9

10. Hypothalamus
• Hormones
– Oxytocin
– Antidiuretic hormone (ADH)
• Hormones transported to the posterior
pituitary for storage
• Directs posterior pituitary to release
hormones
34-10
Glands

11. Pituitary Gland
• Controlled by the hypothalamus
• Located at the base of the brain
– Protected by a bony structure called the sella turcica
– The optic chiasm is located just above the pituitary gland
• Carries visual information to the brain for interpretation
• Two lobes
– Anterior lobe
– Posterior lobe
Glands
34-11

12. Pituitary Gland (cont.)
Growth hormone
Stimulates increase in size
of muscles and bones
Luteinizing
Prolactin Stimulates milk
production
Anterior
Lobe
Females: stimulates ovulation
and estrogen production
Males: stimulates testosterone production
Adrenocorticotropic
Stimulates the adrenal cortex
to release its hormones
Thyroid-stimulating
Stimulates the thyroid
gland to release its
hormones
Follicle-stimulating
Females: stimulates estrogen
production and maturation of the ova
Males: stimulates sperm production
34-12

13. Pituitary Gland (cont.)
Oxytocin
Posterior
Lobe
Antidiuretic hormone (ADH)
Stimulates the kidneys to
conserve water
34-13
Females: causes
contraction of the
uterus and ejection of
breast milk
Males: stimulates
contraction of the
prostate and vas
deferens during
sexual arousal

14. Apply Your Knowledge
Match the following:
ANSWER:
D, E Stored in posterior pituitary
___
A. Follicle-stimulating hormone
___ Milk production
B
B. Prolactin
D, E Produced by hypothalmus
___
C. Luteinizing hormone
___ Stimulates sperm production
A
D. ADH
___ Maturation of ova
A
E. Oxytocin
___ Stimulates ovulation
C
Super!
___ Conservation of water
D
___ Production of testosterone
C
___ Contraction of uterus
E
34-14

15. Thyroid Gland and
Parathyroid Glands
Thyroid Gland
Located below the larynx
 Divided into follicles that store some of the hormones

Major hormones
T3 T4
Stimulate protein synthesis and
increase cellular energy
production
Lowers blood calcium levels
by activating osteoblasts that
Glands
build new bone tissue
34-15

16. Thyroid Gland and
Parathyroid Glands (cont.)
• Parathyroid glands
– Four located on the posterior surface of the thyroid
gland
– Secrete parathyroid hormone (PTH)
• Agonist to calcitonin by raising blood calcium levels
through activation of osetoclasts (dissolve bone)
– As bone dissolves, calcium levels in blood increase
Glands
34-16

17. 34-17
Apply Your Knowledge
True or False:
ANSWER:
__ Thyroid hormones stimulate protein synthesis.
T
Thyroid follicles store
__ The thyroid gland does not store hormones. some hormones.
F
__ PTH activates osteoblasts.
F
PTH activates osteoclasts.
__ Calcitonin increases cellular energy production.
F
Thyroid hormone
increases cellular
energy production.
T
__ The four parathyroid glands are located on the thyroid gland.
__ Calcitonin lowers blood calcium levels.
T

18. Adrenal Glands
• Located on top of each kidney
• Divided into the adrenal medulla and adrenal cortex
• Adrenal medulla
– Central portion
– Hormones
• Epinephrine
• Norepinephrine
• Same effects as sympathetic nervous system
Glands
34-18

19. Adrenal Glands (cont.)
• Adrenal cortex
– Outermost portion
– Secretes many hormones, but main ones are
• Aldosterone
– Stimulates body to retain sodium and water
– Important in maintaining BP
• Cortisol
– Released when stressed
– Decreases protein synthesis, resulting in slowed tissue
repair
– Decreases inflammation
34-19

20. Apply Your Knowledge
Match the following:
ANSWER:
____ Adrenal medulla
B, D
A. Cortisol
C
____ Sodium retention
B. Epinephrine
A
____ Decreases inflammation
C. Aldosterone
B, D
____ Sympathetic effects
D. Norepinephrine
____ Maintains blood pressure
C
Excellent!
____ Released during stress
A
A, C
____ Adrenal cortex
34-20

21. 34-21
Pancreas
• Located behind the
stomach
• Both exocrine gland and
endocrine gland
– Exocrine – secretes
digestive enzymes into a
duct leading to the small
intestine
– Endocrine – secretes
hormones into bloodstream
Glands

22. Pancreas (cont.)
• Islets of Langerhans secrete hormones into
bloodstream
– Alpha cells secrete glucagon
– Beta cells secrete insulin
Blood glucose
concentrations
Blood glucose
concentrations
Protein synthesis
Protein synthesis
34-22

23. Apply Your Knowledge
What are the effects of insulin and glucagon?
ANSWER: Insulin decreases blood glucose concentration and
increases protein synthesis.
Glucagon does just the opposite. It increases blood glucose
and decreases protein synthesis.
Yippee
!
34-23

24. Other Hormone-Producing
Organs
• Pineal body
• Thymus gland
– Small gland
– Located between
cerebral hemispheres
– Melatonin
– Located between
lungs
– Thymosin
• Promotes
production of
T lymphocytes
• Regulates circadian
rhythms
• May play a role in
onset of puberty
Glands
34-24

25. Other Hormone-Producing
Organs (cont.)
• The gonads
• Small intestine
– Ovaries
– Secretin
– Cholecystokinin
• Estrogen
• Progesterone
– Testes
• Heart
– Atrial natriuretic
peptide – regulates BP
• Testosterone
• Stomach
– Gastrin
• Kidneys
– Erythropoietin –
stimulates blood cell
production
34-25
Glands

26. Back
34-26

27. Apply Your Knowledge
Match the following:
ANSWER:
D
___ Between lungs
A. Pineal body
A
___ Melatonin
B. Heart
G
___ Estrogen/testosterone
C. Kidneys
F
___ Gastrin
D. Thymus gland
E
___ Secretin
E. Small intestine
C
___ Erythropoietin
F. Stomach
B
___ Atrial natriuetic peptide
G. Gonads
D
___ Thymosin
E
___ Cholecystokinin
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28. 34-28
The Stress Response
• Stressor
– Any stimulus that
produces stress
– Types
• Physical factors
• Psychological factors
• Positive stimuli

29. The Stress Response (cont.)
• Physiologic response to stress caused by
hormone release
– General stress syndrome
• Increased heart rate, respiratory rate, and BP
• Increase in glucose and fatty acids in blood, which
leads to weight loss
• Increase in cortisol if stress prolonged
– Decreased body repair
– Susceptibility to illness
34-29

30. Apply Your Knowledge
Match the following:
ANSWER:
___ Extreme heat
A
A. Physical stress
___ Death of friend
B
B. Psychological stress
___ Fractured leg
A
C. Positive stimulus
___ Wedding
C
___ Exam
B
___ Hearing an explosion nearby
B
___ “A” on an exam
C
___ Flu
A
___ Car stolen
B
34-30

31. 34-31
Common Diseases and Disorders
Disease/Disorder
Acromegaly
Description
Too much growth hormone produced in adults;
enlargement of bones and thickened skin
Addison’s disease Adrenal gland fails to produce enough
corticosteroids
Cretinism
Extreme form of hypothyroidism present prior
to or soon after birth
Cushing’s disease Hypercortisolism; over-production of cortisol
Diabetes insipidus Kidneys fail to reabsorb water, resulting in
excessive urination; hyposecretion of ADH

32. 34-32
Common Diseases and Disorders
(cont.)
Disease/Disorder
Diabetes mellitus
Description
Chronic disease characterized by elevated
blood glucose levels
Type I
Insulin-dependent diabetes mellitus; usually develops
in childhood
Noninsulin-dependent diabetes mellitus; primarily in
adults but increased incidence in teens
Occurs during pregnancy; usually temporary
Type II
Gestational
Dwarfism
Too little growth hormone (somatotropin)
produced during childhood

33. 34-33
Common Diseases and Disorders
(cont.)
Disease/Disorder Description
Gigantism
Too much growth hormone produced during
childhood
Goiter
Enlargement of thyroid gland, causing
swelling in neck; deficiency of iodine in diet
Grave’s disease
Hyperthyroidism; antibodies attach to thyroid
gland, causing it to produce too much thyroid
hormone
Thyroid gland produces inadequate amounts of
thyroid hormone; common in females over 50
Myxedema

34. Apply Your KnowledgeCorrect!
True or False:
ANSWER:
in an adult
___ Acromegaly develops as a result of too much growth hormone in a child.
F
T
___ In diabetes insipidus, the kidneys fail to reabsorb water.
___ Too little growth hormone in childhood results in dwarfism.
T
___ Myxedema is the result of hyperthyroidism.
F
hypothyroidism
___ Addison’s disease is the result of too little corticosteroid.
T
___ Cushing’s disease is the result of too little ACTH.
F
too much ACTH
___ Cretinism is an extreme form of hyperthyroidism present at birth.
F
hypothyroidism
34-34

35. In Summary
• The organs of the
endocrine system
secrete hormones
directly into blood and
other body fluids.
• Hormones secreted by
the endocrine system
control the functions
of other cells.
• Endocrine organs
–
–
–
–
–
–
–
–
–
34-35
Hypothalamus
Pituitary gland
Thyroid gland
Parathyroid glands
Adrenal glands
Pancreas
Pineal body
Thymus gland
Gonads, stomach small
intestine, heart,
kidneys