Download hormones. - Mrs. Brenner`s Biology

Biology
Sylvia S. Mader
Michael Windelspecht
Chapter 40
Hormones and Endocrine
Systems
Lecture Outline
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Outline
• 40.1 Animal Hormones
• 40.2 Hypothalamus and Pituitary Gland
• 40.3 Other Endocrine Glands and
Hormones
2
40.1 Animal Hormones
– An endocrine system consists of glands that
coordinate body activities through hormones.
• Carried by the bloodstream to target cells throughout
the body
– Endocrine glands can be contrasted with exocrine
glands
• Endocrine glands – secrete products directly into the
bloodstream
• Exocrine glands – secrete products into ducts, which
subsequently take them to lumens of other organs or
outside the body
3
Animal Hormones
– Hormones influence homeostatic functions of an
organism
• Metabolism, growth, reproduction, osmoregulation,
digestion, etc
– Hormones control processes unique to
invertebrates
• Ex: metamorphosis
4
Modes of Action of the Nervous
and Endocrine Systems
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liver cell
liver
insulin
receptor
b. Reception of insulin, a hormone
axon of
nerve fiber
pancreas
arteriole
vesicle
axon terminal
neurotransmitter
receptor
a. Reception of a neurotransmitter
5
Major Glands of The Human Endocrine System
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testis
(male)
6
ovary (female)
Major Glands of The Human Endocrine System
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testis
(male)
7
ovary (female)
Major Glands of The Human Endocrine System
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HYPOTHALAMUS
Releasing and inhibiting hormones:
regulate the anterior pituitary
testis
(male)
8
ovary (female)
Major Glands of The Human Endocrine System
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HYPOTHALAMUS
Releasing and inhibiting hormones:
regulate the anterior pituitary
PITUITARY GLAND
Posterior Pituitary
Antidiuretic (ADH):
water reabsorption by kidneys
Oxytocin: stimulates uterine
contraction and milk letdown
Anterior Pituitary
Thyroid stimulating (TSH):
stimulates thyroid
Adrenocorticotropic (ACTH):
stimulates adrenal cortex
Gonadotropic (FSH, LH): egg and
sperm production; sex hormone
production
Prolactin (PL): milk production
Growth (GH): bone growth, protein
synthesis, and cell division
testis
(male)
9
ovary (female)
Major Glands of The Human Endocrine System
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
HYPOTHALAMUS
Releasing and inhibiting hormones:
regulate the anterior pituitary
PITUITARY GLAND
Posterior Pituitary
Antidiuretic (ADH):
water reabsorption by kidneys
Oxytocin: stimulates uterine
contraction and milk letdown
Anterior Pituitary
Thyroid stimulating (TSH):
stimulates thyroid
Adrenocorticotropic (ACTH):
stimulates adrenal cortex
Gonadotropic (FSH, LH): egg and
sperm production; sex hormone
production
Prolactin (PL): milk production
Growth (GH): bone growth, protein
synthesis, and cell division
THYROID
Thyroxine (T4) and triiodothyronine
(T3): increase metabolic rate;
regulates growth and development
Calcitonin: lowers blood calcium level
testis
(male)
10
ovary (female)
Major Glands of The Human Endocrine System
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
HYPOTHALAMUS
Releasing and inhibiting hormones:
regulate the anterior pituitary
PITUITARY GLAND
Posterior Pituitary
Antidiuretic (ADH):
water reabsorption by kidneys
Oxytocin: stimulates uterine
contraction and milk letdown
Anterior Pituitary
Thyroid stimulating (TSH):
stimulates thyroid
Adrenocorticotropic (ACTH):
stimulates adrenal cortex
Gonadotropic (FSH, LH): egg and
sperm production; sex hormone
production
Prolactin (PL): milk production
PINEAL GLAND
Melatonin: controls circadian
and circannual rhythms
Growth (GH): bone growth, protein
synthesis, and cell division
PARATHYROIDS
Parathyroid hormone (PTH):
raises blood calcium level
parathyroid glands
(posterior surface
of thyroid)
THYROID
Thyroxine (T4) and triiodothyronine
(T3): increase metabolic rate;
regulates growth and development
Calcitonin: lowers blood calcium level
testis
(male)
11
ovary (female)
Major Glands of The Human Endocrine System
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
HYPOTHALAMUS
Releasing and inhibiting hormones:
regulate the anterior pituitary
PITUITARY GLAND
Posterior Pituitary
Antidiuretic (ADH):
water reabsorption by kidneys
Oxytocin: stimulates uterine
contraction and milk letdown
Anterior Pituitary
Thyroid stimulating (TSH):
stimulates thyroid
Adrenocorticotropic (ACTH):
stimulates adrenal cortex
Gonadotropic (FSH, LH): egg and
sperm production; sex hormone
production
Prolactin (PL): milk production
PINEAL GLAND
Melatonin: controls circadian
and circannual rhythms
Growth (GH): bone growth, protein
synthesis, and cell division
PARATHYROIDS
Parathyroid hormone (PTH):
raises blood calcium level
parathyroid glands
(posterior surface
of thyroid)
THYROID
Thyroxine (T4) and triiodothyronine
(T3): increase metabolic rate;
regulates growth and development
Calcitonin: lowers blood calcium level
ADRENAL GLAND
Adrenal cortex
Glucocorticoids (cortisol):
raises blood glucose level;
stimulates breakdown of protein
Mineralocorticoids (aldosterone):
reabsorption of sodium and
excretion of potassium
Sex hormones: reproductive organs
and bring about sex characteristics
Adrenal medulla
Epinephrine and norepinephrine:
active in emergency situations;
raise blood glucose level
testis
(male)
12
ovary (female)
Major Glands of The Human Endocrine System
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
HYPOTHALAMUS
Releasing and inhibiting hormones:
regulate the anterior pituitary
PITUITARY GLAND
Posterior Pituitary
Antidiuretic (ADH):
water reabsorption by kidneys
Oxytocin: stimulates uterine
contraction and milk letdown
Anterior Pituitary
Thyroid stimulating (TSH):
stimulates thyroid
Adrenocorticotropic (ACTH):
stimulates adrenal cortex
Gonadotropic (FSH, LH): egg and
sperm production; sex hormone
production
Prolactin (PL): milk production
PINEAL GLAND
Melatonin: controls circadian
and circannual rhythms
Growth (GH): bone growth, protein
synthesis, and cell division
PARATHYROIDS
Parathyroid hormone (PTH):
raises blood calcium level
parathyroid glands
(posterior surface
of thyroid)
THYROID
Thyroxine (T4) and triiodothyronine
(T3): increase metabolic rate;
regulates growth and development
Calcitonin: lowers blood calcium level
THYMUS
Thymosins: production
and maturation of T
lymphocytes
ADRENAL GLAND
Adrenal cortex
Glucocorticoids (cortisol):
raises blood glucose level;
stimulates breakdown of protein
Mineralocorticoids (aldosterone):
reabsorption of sodium and
excretion of potassium
Sex hormones: reproductive organs
and bring about sex characteristics
Adrenal medulla
Epinephrine and norepinephrine:
active in emergency situations;
raise blood glucose level
testis
(male)
13
ovary (female)
Major Glands of The Human Endocrine System
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
HYPOTHALAMUS
Releasing and inhibiting hormones:
regulate the anterior pituitary
PITUITARY GLAND
Posterior Pituitary
Antidiuretic (ADH):
water reabsorption by kidneys
Oxytocin: stimulates uterine
contraction and milk letdown
Anterior Pituitary
Thyroid stimulating (TSH):
stimulates thyroid
Adrenocorticotropic (ACTH):
stimulates adrenal cortex
Gonadotropic (FSH, LH): egg and
sperm production; sex hormone
production
Prolactin (PL): milk production
PINEAL GLAND
Melatonin: controls circadian
and circannual rhythms
Growth (GH): bone growth, protein
synthesis, and cell division
PARATHYROIDS
Parathyroid hormone (PTH):
raises blood calcium level
parathyroid glands
(posterior surface
of thyroid)
THYROID
Thyroxine (T4) and triiodothyronine
(T3): increase metabolic rate;
regulates growth and development
Calcitonin: lowers blood calcium level
THYMUS
Thymosins: production
and maturation of T
lymphocytes
ADRENAL GLAND
Adrenal cortex
Glucocorticoids (cortisol):
raises blood glucose level;
stimulates breakdown of protein
Mineralocorticoids (aldosterone):
reabsorption of sodium and
excretion of potassium
Sex hormones: reproductive organs
and bring about sex characteristics
PANCREAS
Adrenal medulla
Epinephrine and norepinephrine:
active in emergency situations;
raise blood glucose level
testis
(male)
Insulin: lowers blood
glucose level and
promotes glycogen
buildup
Glucagon: raises blood
glucose level and
promotes glycogen
breakdown
14
ovary (female)
Major Glands of The Human Endocrine System
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
HYPOTHALAMUS
Releasing and inhibiting hormones:
regulate the anterior pituitary
PITUITARY GLAND
Posterior Pituitary
Antidiuretic (ADH):
water reabsorption by kidneys
Oxytocin: stimulates uterine
contraction and milk letdown
Anterior Pituitary
Thyroid stimulating (TSH):
stimulates thyroid
Adrenocorticotropic (ACTH):
stimulates adrenal cortex
Gonadotropic (FSH, LH): egg and
sperm production; sex hormone
production
Prolactin (PL): milk production
PINEAL GLAND
Melatonin: controls circadian
and circannual rhythms
Growth (GH): bone growth, protein
synthesis, and cell division
PARATHYROIDS
Parathyroid hormone (PTH):
raises blood calcium level
parathyroid glands
(posterior surface
of thyroid)
THYROID
Thyroxine (T4) and triiodothyronine
(T3): increase metabolic rate;
regulates growth and development
Calcitonin: lowers blood calcium level
THYMUS
Thymosins: production
and maturation of T
lymphocytes
ADRENAL GLAND
Adrenal cortex
Glucocorticoids (cortisol):
raises blood glucose level;
stimulates breakdown of protein
Mineralocorticoids (aldosterone):
reabsorption of sodium and
excretion of potassium
Sex hormones: reproductive organs
and bring about sex characteristics
PANCREAS
Insulin: lowers blood
glucose level and
promotes glycogen
buildup
Glucagon: raises blood
glucose level and
promotes glycogen
breakdown
Adrenal medulla
Epinephrine and norepinephrine:
active in emergency situations;
raise blood glucose level
testis
(male)
GONADS
Testes
Androgens (testosterone):
male sex characteristics
Ovaries
ovary (female)
Estrogens and progesterone:
female sex characteristics
15
Animal Hormones
• Hormones are Chemical Signals
• Pheromones
– Chemical signals that influence the behavior of
other individuals
– A woman’s axillary extract can alter another
woman’s menstrual cycle
16
Target Cell Concept
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nontarget cell
receptors
target cells
hormone
capillary
17
Animal Hormones
• The Action of Hormones
• Peptide hormones
• Peptides, proteins, glycoproteins, and modified amino acids
• Most bind to receptors on the plasma membrane
• First messenger – hormone that never enters a cell
• Causes internal release of cAMP
• Second messenger that functions to set the metabolic machinery
in motion.
• Steroid hormones
• All derived from cholesterol
• Enter the cell by moving through the plasma membrane
rather than binding to receptor proteins
18
Epinephrine, a Peptide Hormone
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19
Epinephrine, a Peptide Hormone
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20
Epinephrine, a Peptide Hormone
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peptide hormone
(epinephrine)
21
Epinephrine, a Peptide Hormone
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
peptide hormone
(epinephrine)
22
Epinephrine, a Peptide Hormone
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
1. Epinephrine binds to a
receptor in the plasma
membrane.
peptide hormone
(epinephrine)
receptor protein
23
Epinephrine, a Peptide Hormone
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1. Epinephrine binds to a
receptor in the plasma
membrane.
peptide hormone
(epinephrine)
activated
enzyme
receptor protein
2. Binding leads to
activation of an
enzyme that changes
ATP to cAMP.
ATP
cAMP
(second messenger)
24
Epinephrine, a Peptide Hormone
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
1. Epinephrine binds to a
receptor in the plasma
membrane.
peptide hormone
(epinephrine)
activated
enzyme
receptor protein
2. Binding leads to
activation of an
enzyme that changes
ATP to cAMP.
ATP
cAMP
(second messenger)
3. cAMP activates an
enzyme cascade.
25
Epinephrine, a Peptide Hormone
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capillary
1. Epinephrine binds to a
receptor in the plasma
membrane.
peptide hormone
(epinephrine)
activated
enzyme
receptor protein
2. Binding leads to
activation of an
enzyme that changes
ATP to cAMP.
plasma
membrane
cAMP
(second messenger)
ATP
3. cAMP activates an
enzyme cascade.
4. Many molecules of
glycogen are broken
down to glucose,
which enters the
bloodstream.
glucose
(leaves cell
and goes
to blood)
glycogen
26
Steroid Hormone
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steroid
hormone
1. Hormone diffuses
through plasma
membrane because
it is lipid soluble.
plasma
membrane
cytoplasm
nuclear
pore
nucleus
2. Hormone binds
to receptor inside
nucleus.
protein
DNA
receptor
protein
mRNA
3. Hormone-receptor
complex activates
gene and synthesis
of a specific mRN
molecule.
ribosome
mRNA
4. mRNA moves to
ribosomes, and protein
synthesis occurs.
27
40.2 Hypothalamus and
Pituitary Gland
• The hypothalamus regulates internal environment
• Acts through autonomic system
• Also controls the glandular secretions of pituitary
gland
– Posterior Pituitary
• Produces antidiuretic hormone (ADH)
– Controlled by negative feedback
– Effect of the hormone acts to shut down the release
of the hormone
• Produces oxytocin
• Controlled by positive feedback
• Stimulus continues to bring about an effect that ever
increases intensity
28
Hypothalamus and Pituitary
Gland
• Anterior Pituitary
• Controlled by the hypothalamus, which produces
– Hypothalamic-releasing hormones
– Hypothalamic-inhibiting hormones
• Anterior pituitary hormones that affect other glands:
• Thyroid-Stimulating Hormone (TSH)
• Adrenocorticotropic Hormone (ACTH)
• Gonadotropic Hormones
• Anterior pituitary hormones that do NOT affect other
glands
• Prolactin (PRL)
• Melanocyte-Stimulating Hormone (MSH)
• Growth Hormone (GH)
29
Hypothalamus and the Pituitary
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hypothalamus
1. Neurosecretory cells produce
hypothalamic-releasing and
hypothalamic-inhibiting hormones.
2. These hormones are secreted into
a portal system.
1. Neurosecretory cells produce ADH
and oxytocin.
optic
chiasm
2. These hormones move down
axons to axon endings.
portal system
4. The anterior pituitary secretes
its hormones into the bloodstream,
whereby they are then delivered to
specific cells, tissues, and glands.
3. When appropriate, ADH and
oxytocin are secreted from axon
endings into the bloodstream.
Posterior pituitary
Kidney tubules:
antidiuretic
hormone (ADH)
Smooth muscle
in uterus:
oxytocin
3. Each type of hypothalamic
hormone either stimulates or
inhibits production and secretion
of an anterior pituitary hormone.
Mammary glands:
oxytocin
Anterior pituitary
Mammary glands:
prolactin (PRL)
Thyroid:
thyroid-stimulating
hormone (TSH)
Adrenal cortex:
adrenocorticotropic
hormone (ACTH)
Bones, tissues:
growth hormone
(GH)
Ovaries, testes:
gonadotropic
hormones (FSH, LH)
30
Effect of Growth Hormone
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a.
b.
a: © AP/Wide World Photos; b: © Ewing Galloway, Inc.
31
Acromegaly
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Age 9
Age 16
Age 33
Age 52
From Clinical Pathological Conference, "Acromegaly, Diabetes, Hypermetabolism, Proteinura and Heart Failure", American Journal of Medicine, 20 (1956) 133. Reprinted with permission from
Excerpta Medica Inc.
32
40.3 Other Endocrine Glands
and Hormones
• Thyroid and Parathyroid Glands
• Thyroid Gland
• Attached to the trachea just below the larynx
• Composed of a large number of follicles filled with
– Triiodothyronine (T3) and Thyroxine (T4)
• These hormones function to increase the metabolic rate by stimulating most
of the body cells to metabolize at a faster rate
• Thyroid acquires iodine to produce these compounds
• Thyroid-induced abnormalities
– Simple goiter - Poor hormone production
– Cretinism - Poor thyroid development
– Myxedema - Hypothyroidism
– Exophthalmic goiter - Hyperthyroidism
33
Other Endocrine Glands and
Hormones
• Thyroid and Parathyroid Glands
• Thyroid-induced abnormalities
• Simple goiter – poor hormone production
• Congenital hypothyroidism (cretinism) – poor thyroid
development
• Hypothyroidism – immune system produces antibodies that
destroy the thyroid gland
• Untreated hypothyroidism results in myxedema
• Lethargy, weight loss, loss of hair, slow heart rate, lowered body
temperature, thickness and puffiness of skin
• Hyperthyroidism – oversecretion of T3 or T4
• Graves disease – antibodies stimulate overproduction of T3 and T4
• Exophthalmos – excessive protrusion of eyes
34
Abnormalities of the Thyroid
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affected eye
a. Simple goiter
b. Congenital hypothyroidism
c. Exophthalmic goiter
a: © Bruce Coleman, Inc./Alamy; b: © Medical-on-Line/Alamy; c: © Dr. P. Marazzi/Photo Researchers, Inc.
35
Other Endocrine Glands and
Hormones
• Effects of Calcitonin
• Regulates blood calcium level (in part)
• Secreted by the thyroid gland when blood calcium
level rises
• Brings about deposit of calcium in the bones
36
Other Endocrine Glands and
Hormones
• Parathyroid Glands
• Low calcium level in blood stimulates the release of
parathyroid hormone (PTH) by the parathyroid
glands
– Parathyroid hormone causes
• Phosphate level in blood to decrease, and
• Calcium level in blood to increase
– Insufficient production of parathyroid hormone leads to tetany
37
Regulation of Blood Calcium Level
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
calcitonin
Thyroid gland
secretes
calcitonin
into blood.
Bones
take up Ca2+
from blood.
Blood Ca2+
lowers.
Homeostasis (normal blood Ca2+)
Blood Ca2+
rises.
Parathyroid
glands
release PTH
into blood.
activated
vitamin D
parathyroid
hormone
(PTH)
Intestines
absorb Ca2+
from digestive
tract.
Kidneys
reabsorb Ca2+
from kidney
tubules.
Bones
release Ca2+
into blood.
38
Other Endocrine Glands and
Hormones
• Adrenal Glands
• Paired
• One sits atop each kidney
• Each consists of an outer cortex and inner
medulla
• Adrenal medulla
• Produces epinephrine and norepinephrine
• Adrenal cortex
• Produces mineralocorticoids and glucocorticoids
39
Adrenal Glands
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stress
hypothalamus
spinal cord
(cross section)
neurosecretory
cells produce
hypothalamicreleasing
hormone
path of nerve
impulses
epinephrine
Glucocorticoids
Protein and fat metabolism
instead of glucose
breakdown.
neuron
cell body
sympathetic fibers
Stress Response:
Long Term
anterior
pituitary
secretes
ACTH
ACTH
Reduction of inflammation;
immune cells are
suppressed.
Mineralocorticoids
Sodium ions and water
are reabsorbed by kidney.
norepinephrine
Blood volume and
pressure increase.
Stress Response:
Short Term
Heartbeat and blood
pressure increase.
glucocorticoids
Blood glucose level rises.
mineralocorticoids
Muscles become
energized.
adrenal medulla
adrenal cortex
40
Other Endocrine Glands and
Hormones
• Glucocorticoids
– Cortisol
• Raises blood glucose level
• Promotes breakdown of muscle proteins to amino
acids
• Promotes metabolism of fatty acids
• Counteracts inflammatory response
41
Other Endocrine Glands and
Hormones
• Mineralocorticoids
– Aldosterone
• Promotes two renal functions:
– Absorption of sodium
– Excretion of potassium
– Atrial natriuretic hormone (ANH)
• Inhibits secretion of aldosterone
• Causes excretion of sodium ions (natriuresis)
– Renin-angiotensin-aldosterone system
• Raises blood pressure
• Angiotensin II constricts arterioles
• Aldosterone causes kidneys to reabsorb sodium (causing
water retention)
42
Regulation of Blood Pressure and
Volume
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atrial natriuretic
hormone (ANH)
Kidneys excrete
Na+ and water
in urine.
Heart secretes
atrial natriuretic
hormone (ANH)
into blood.
Blood pressure
lowers.
Homeostasis (normal blood pressure)
Blood pressure
rises.
Kidneys secrete
renin into blood.
Kidneys
reabsorb Na+
and water from
kidney tubules.
renin
angiotensin
I and II
aldosterone
Adrenal cortex
secretes
aldosterone
into blood.
43
Other Endocrine Glands and
Hormones
• Malfunctions of the Adrenal Cortex
• Addison disease
• Insufficient secretion of hormones by adrenal
cortex
• Dehydration, weakness, weight loss, hypotension
• Cushing syndrome
• Excessive levels of glucocorticoids
• Causes metabolism of muscle protein and deposition of
subcutaneous gat in the midsection
44
Addison Disease
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a.
b.
a: © Custom Medical Stock Photos; b: © NMSB/Custom Medical Stock Photos
45
Cushing Syndrome
46
Other Endocrine Glands and
Hormones
• Pancreas
• Made up of exocrine and endocrine tissue
– Endocrine portion of the pancreas:
• Consists of pancreatic islets
• Produce and secrete
– Insulin
» Secreted during high blood glucose level
» Stimulates uptake of glucose by cells
– Glucagon
» Secreted during low blood glucose level
» Stimulates liver to break down glycogen
– Exocrine portion of the pancreas:
• Secretes enzymes and buffers into the small intestine
47
Regulation of Blood Glucose
Level
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
insulin
Liver stores
glucose from
blood as
glycogen.
Pancreatic islet
of Langerhans
Muscle cells
store glycogen
and build protein.
After eating,
pancreas
secretes insulin
into blood.
Adipose tissue
uses glucose
from blood
to form fat.
Blood glucose
level lowers.
Homeostasis (normal blood glucose)
Before eating,
pancreas secretes
glucagon into
blood.
Liver breaks
down glycogen
to glucose.
Glucose enters
blood.
Pancreatic islet
of Langerhans
Adipose tissue
breaks down fat.
glucagon
© Peter Arnold, Inc./Alamy
48
Other Endocrine Glands and
Hormones
• Diabetes Mellitus
• Inability of the body’s cells to take up glucose
as they should
• Causes blood glucose levels to be higher than
normal
• Cells must rely on other sources of energy, such
as fatty acids
• As blood glucose levels rise, glucose, along with
water, is excreted in the urine
• Results in frequent urination and a feeling of
extreme thirst
49
Other Endocrine Glands and
Hormones
• Diabetes Mellitus
• Type 1 Diabetes
• Pancreas does not produce enough insulin
• Body turns to the metabolism of fat, which leads to the
buildup of ketones in the blood
• Patients must have daily insulin injections
• Type 2 Diabetes
• Patients are typically overweight and adipose tissue
produces a substance that impairs insulin receptor function
• Prevented/controlled by adhering to a low-fat diet, low-sugar
diet, and regular exercise
50
Identifying Insulin as a Chemical
Messenger
• In 1920, Frederick Banting and Charles Best
were the first to isolate insulin
• Insulin therapy began in 1922 for human
patients and large-scale production of purified
insulin from pigs and cattle soon followed
• In 1953, the amino acid sequence for insulin
was determined
• Today, insulin is synthesized using recombinant
DNA techniques using the bacterium E. coli to
produce the hormone.
51
Other Endocrine Glands and
Hormones
• Testes and Ovaries
– Testes
• Produce testosterone
• Secondary sex characteristics
• Anabolic steroids mimic the effect of testosterone and
can lead to very dangerous side effects
– Ovaries
• Produce estrogen and progesterone
• Secondary sex characteristics
52
The Effects of Anabolic Steroid
Use
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balding in men and women;
hair on face and chest in
women
deepening of voice in women
breast enlargement in men
and breast reduction in women
'roid rage–
delusions and hallucinations;
depression upon withdrawal;
violent or aggressive behavior
severe acne
high blood cholesterol and
atherosclerosis; high blood
pressure and damage to heart
liver dysfunction
and cancer
kidney disease and
retention of fluids,
called "steroid bloat"
reduced testicular
size, low sperm count,
and impotency
in women, increased
size of ovaries;
cessation of ovulation
and menstruation
stunted growth in
adolescents by Prematurely halting Fusion
of the growth plates
53
Other Endocrine Glands and
Hormones
• Pineal Gland
– Produces melatonin
• Involved in daily sleep-wake cycle (circadian
rhythms)
– Controlled by an internal biological clock
• Thymus Gland
– Most active during childhood
– Aids in differentiation of lymphocytes
54
Melatonin Production
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a. experimental
b. winter
6 P.M.
6 A.M.
c. summer
© The McGraw-Hill Companies, Inc./ Evelyn Jo Johnson, photographer
55
Other Endocrine Glands and
Hormones
• Leptin
– Secreted by adipose tissue
– Involved in feedback control of appetite
• Erythropoietin
– Produced by the kidneys
– Stimulates production of red blood cells
• Prostaglandins
– Local hormones
– Not distributed in blood
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