Anatomy and Physiology II Student Outline – The Endocrine System
The Endocrine System
1.
Introduction
A.
Endocrine Glands
•
2.
Endocrine vs. Exocrine Glands
B.
Hormones
C.
Target Tissues / Cells
Basic Functions
A.
Maintenance of Homeostasis
B.
Regulatory Functions
i.
ii.
iii.
3.
Growth
Development
Reproductive Matters
Biochemistry of Hormones
A.
Steroids
CH 3 CH3
CH2OH
CH
CH
CH 2
CH 2
CH
Cholesterol
CH
CH3
CH
CH
2
C
3
O
Cortisol
OH
O CH2OH
3
CH3
H
HO
C
C
O
HO
3
Aldosterone
HO
B.
HO
Amines
Radical Group
R
Amino Group
NH 2
C
OH
O
C
Tyros ine
CH2
Acid Group
NH2
OH
H
C
H
O
C
OH
Bas ic Amino Acid
H
Epinephrine
NH 2
OH
C
C
H
H
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OH
OH
NH2
H
H
OH
C
C
C
H
H
OH
OH
Norepinephrine
Anatomy and Physiology II Student Outline – The Endocrine System
C.
Peptides
•
•
Antidiuretic Hormone
Oxytocin
Oxytocin
Tyr
Cy s
Ileu
Glu
4.
Cy s Pro Leu Gly
Glu
Cy s Pro Arg Gly
As p
Proteins
Glycoproteins
Feedback Control System
A.
Negative Feedback System (See Endocrine Pathways Handout: “Control
Paradigm (Negative Feedback System))
i.
B.
Example: (See Endocrine Pathways Handout: “Negative
Feedback Example”)
Positive Feedback System (See Endocrine Pathways Handout: “Positive
Feedback Example”)
i.
5.
Cy s
Phe
As p
D.
E.
Antidiuretic Hormone
Tyr
Child Birth and Oxytocin
Mechanisms of Hormone Control
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Anatomy and Physiology II Student Outline – The Endocrine System
A.
Fixed-Membrane-Receptor Mechanism
ii.
Mechanism
ATP
Inacti ve
Enzyme 1
cAMP
(Second ary
Mess enge r)
Acti ve
Enzyme 1
Inacti ve
Enzyme 4
Al tered
Cell Fun cti on
ii.
B.
Acti ve
Enzyme 4
Examples
Mobile-Receptor Mechanism
C
D
F
B
G
A
6.
Pituitary Gland
A.
Posterior Lobe (Neurohypophysis)
i.
Neurosecretory Cells
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E
Inacti ve
Enzyme 2
Acti ve
Enzyme 2
Inacti ve
Acti ve Enzyme 3
Enzyme 3
Anatomy and Physiology II Student Outline – The Endocrine System
ii.
•
ADH Supraoptic Nucleus  ADH
•
Oxytocin Paraventricular Nucleus  Oxytocin
•
Infundibulum
Hormones of the Neurohypophysis
a.
Antidiuretic Hormone (ADH) (or Vasopressin)
•
(See Endocrine Pathways Handout: “Water
Balance and Antidiuretic Hormone (ADH)”)
•
Diuretic
•
b.
Oxytocin
•
(See Endocrine Pathways Handout:
“Positive Feedback Example”)
•
Myoepithelial Cells
•
B.
Antidiuretic
Positive Feedback Mechanism
Anterior Lobe (Adenohypophysis)
Hypothalamus secretes
stimulating Hormones
Hypo tha la mic-h ypo ph esea l
Po rtal Vein
Pituitary Gland in response to
stimulating hormones secretes
tropic or non-tropic hormones
into the blood stream.
i.
ii.
Anterior Pituitary Gland
Hypothalamic-Hypophyseal Portal System
Hormones of the Adenohypophysis
•
Tropic and Non-tropic Hormones
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Anatomy and Physiology II Student Outline – The Endocrine System
Endocrine Gland
Tropic Hormone
Endocrine Gland
Endocrine Gland
Non-tropic Hormone
Target
Tissue
Target
Tissue
** Response **
** Response **
i.
Non-Tropic Hormones
a.
Growth Hormone (GH)
*
(See Endocrine Pathways Handout:
“Growth Hormone”)
•
Nontropic.
•
Anabolic Effect
•
Amino Acid Uptake Increase
•
Fat Metabolism
•
Epiphyseal Plate
•
ii.
*
Dwarfism
*
Acromegaly
Mechanism
*
Growth-Hormone Releasing Hormone (GHRH)
*
Growth-Hormone Inhibiting Hormone (GHIH)
Some Tropic Hormones
a.
b.
Prolactin
•
Females
*
Mammary Gland Development
*
Milk Production
•
Males
Follicle-Stimulating Hormone (FSH)
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Anatomy and Physiology II Student Outline – The Endocrine System
•
c.
g.
7.
Females
*
Follicle Development
•
Males
Luteinizing Hormone (LH)
•
Females
*
Ovulation
•
Males
*
Interstitial Cells
*
Testosterone
*
Gonadotropin-Releasing Hormone (GnRH)
Melanocyte-Stimulating Hormone (MSH)
Thyroid Gland (Follicles of gland)
*
(See Endocrine Pathways Handout:
“Thyroxin and the Basal Metabolic Rate
(BMR)”)
page #7 (??)
•
Follicular Cells
A.
Thyroxine and Triiodothyronine
Thyroxine (T4)
i.
ii.
iii.
iv.
Triiodothyronine (T3)
Structure
a.
Follicles
b.
Colloid
Synthesis
a.
Tyrosine
b.
Iodine
Function
a.
Increase Metabolism
b.
Calorigenic Effect
Thyroid Malfunction
a.
Hyperthyroidism
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Anatomy and Physiology II Student Outline – The Endocrine System
b.
Hypothyroidism
c.
Goiter
*
(Pull out Handout: (Iodine and Goiter”)
v.
Synthesis of Thyroid Hormone
vi.
An Alternative diagram for Thyroid regulation:
Metabolic Rate
Slows Down
Thyroid Secretes
Less Thyroxine
Decreases Neg. Feedback
Pituitary Secretes
Less TSH
Hypothalamus Releases
More TRH
Pituitary Secretes
More TSH
Hypothalamus Releases
Less TRH
Increases Neg. Feedback
Thyroid Secretes
More Thyroxin
Metabolic Rate
Speeds Up
8.
Parathyroid Glands AND Thyroid Gland (Parafollicular cells NOT Follicles)
*
(See Endocrine Pathways Handout:
“Calcium Regulation in the Blood”)
A.
Parathyroid Hormone
B.
9.
i.
Function
ii.
Mechanisms
a.
Calcium Reabsorption
b.
Kidney Reabsorption
c.
Digestive Absorption of Calcium
Parafollicular Cells of Thyroid Gland
Adrenal Glands
*
(See Endocrine Pathways Handout:
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Anatomy and Physiology II Student Outline – The Endocrine System
“Adrenal Gland and Stress”)
•
Medulla
•
A.
Cortex
Adrenal Cortex
i.
General Information
ii.
Anatomy
a.
b.
c.
iii.
Zona Glomerulosa
Zona Fasciculata
Zona Reticularis
Hormones of the Adrenal Gland
a.
b.
Glucocorticoids
•
Gluconeogenesis
•
Cortisol and Corticosterone
•
Corticotropin-Releasing Hormone (CRH)
Mineralocorticoid
•
B.
Aldosterone
Adrenal Medulla
*
(Again, see Endocrine Pathways Handout:
“Adrenal Gland and Stress”)
i.
ii.
Hormones
a.
Epinephrine
b.
Norepinephrine
Stress and the Adrenal Cortex
STRESS
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Anatomy and Physiology II Student Outline – The Endocrine System
Adrenal medulla
secretes epinephrine
and norepinephrine
Sympathetic
nerve
impulses
Hypothalamus
Blood Glucose
Heart Rate
Respiration
Secretes CRH
Rises
Increases
Rate increases
(Corticotropin Rel. Hor.)
Blood flow to
Blood Pressure
Bronchioles
skeletal muscles
Rises
dilate
increases
Adenohypophysis
secretes ACTH
Adrenal cortex
secretes cortisol
Protein is used
for energy and
tissue repair
10.
Insulin to brain
to ensure
Pancreas
*
(See Endocrine Pathways Handout: “Glucose Regulation”)
A.
Introduction
i.
Mixed Gland
a.
Exocrine Gland
b.
Endocrine Gland
•
Pancreatic Islets
B.
Hormones
i.
Glucagon
a.
ii.
11.
Gluconeogenesis
for energy
glucose supply
Alpha Cells
Insulin - a peptide
a.
Beta Cells
•
Ovaries
Gonads
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Anatomy and Physiology II Student Outline – The Endocrine System
•
Testes
Male Sex Hormones
i.
Testosterone
ii.
Luteinizing Hormone (LH)
iii.
Follicle-Stimulating Hormone (FSH).
iv.
Inhibin
B.
Female Sex Hormones
i.
Estrogens
ii.
Relaxin
i.
Follicle-stimulating hormone
ii.
Luteinizing hormone
Other Sources of Hormones
A.
12.
A.
Kidneys
i.
Renin
ii.
Erythropoietin
*
(See Endocrine Pathways Handout:
“Oxygen Carrying Capacity of Blood”)
B.
Pineal Gland
i.
Melatonin
Thymus Gland
Digestive System
i.
Gastrin
ii.
Secretin
iii.
Cholecystokinin
Placenta
C.
D.
E.
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