Ch3

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CHAPTER 3
INFLAMMATION, THE INFLAMMATORY
RESPONSE, AND FEVER
PRE LECTURE QUIZ
TRUE/FALSE
T

Acute inflammation is the immediate and early response to
an injurious agent and occurs in two phases; the vascular
phase and the cellular phase.
T

Chronic inflammation is self-perpetuating and may last for
weeks, months, or even years.
F

Erythrocytes play a central role in the physiology of
inflammation.
F

Vasoconstriction occurs during the vascular stage of
inflammation.
F

Fever is a pathologic response to bacterial and viral infection
with and has no positive outcome on illness.
PRE LECTURE QUIZ
cardinal
Convection

The ______________ signs of inflammation are known
as redness, swelling, heat, pain, and loss of function.

Histamine, serotonin, cytokines, bradykinin, arachidonic
acid, and platelet-activating factor are _____________
of inflammation.
Fever
hypothalamus Body temperature is regulated by the thermoregulatory
center in the ________________.
mediators
 ____________, or pyrexia, represents an increase in
body temperature due to resetting of the hypothalamic
thermoregulatory set point as the result of endogenous
pyrogens released from host macrophages or
endothelial cells.

_____________ refers to heat transfer through the
circulation of air currents.
INFLAMMATION

Inflammation is an automatic response to cell injury
that:

Neutralizes harmful agents

Removes dead tissue
INFLAMMATION

Damaged cells release
inflammatory mediators.

These compounds
stimulate inflammation.
Damaged cells
release
inflammatory
mediators
local
responses
systemic (wholebody) responses
vascular cellular white blood
stage
stage cell response
acute-phase
response
ACUTE INFLAMMATION

Vascular stage
 Prostaglandins
and leukotrienes affect blood
vessels.
 Arterioles and venules dilate.
º
º
Increasing blood flow to injured area
Redness and warmth result
 Capillaries
º
º
become more permeable.
Allowing exudate to escape into the tissues
Swelling and pain result
QUESTION
What mechanism causes the redness (erythema)
associated with the inflammatory process?
a. Prostaglandins
b. Leukotrienes
c. Arachidonic acid
d. All of the above
e. a and b
ANSWER
a and b
Prostaglandins and leukotrienes cause
vasodilation, which brings more blood to the
injured/affected area. The symptoms caused
by this vasodilation are redness/erythema and
warmth.
e.
KINDS OF EXUDATE

Serous

Hemorrhagic

Fibrinous

Membranous

Purulent
SCENARIO:
A woman has peritonitis …


She has a distended abdomen, low blood pressure, and
fluid in her abdominal cavity.
After surgery, she is told to report any GI distress as it
may indicate fibrous adhesions.
Question:
 What kinds of exudate are involved? What
useful purposes do they serve? What
complications may they cause?
CELLULAR STAGE

White blood cells enter the
injured tissue:
 Destroying infective
organisms
 Removing damaged cells
 Releasing more
inflammatory mediators
to control further
inflammation and healing
WHITE BLOOD CELLS INVOLVED IN
INFLAMMATION


Granulocytes
 Neutrophils
 Eosinophils
 Basophils
 Mast cells
Monocytes
 Monocytes  Macrophages
LEUKOCYTES





Leukocytes enter the injured
area
Leukocytes express adhesive
proteins
Attach to the blood vessel
lining
Squeeze between the cells
Follow the inflammatory
mediators to the injured area
LEUKOCYTES (CONT.)
LEUKOCYTES (CONT.)
Leukocytes release many inflammatory
mediators at the injured area:
 Histamine and serotonin
 Platelet-activating factor
 Cytokines
 Colony-stimulating
factors
 Interleukins
 Interferons
 Tumor

necrosis factor
Nitric oxide
QUESTION
Which leukocytes participate in the acute
inflammatory response?
a. Eosinophils
b. Monocytes
c. Neutrophils
d. All of the above
e. a and c
ANSWER
All of the above
Granulocytes and monocytes play a role in the
acute phase of the immune response.
Eosinophils and neutrophils are granulocytes,
so all of the leukocytes listed participate.
d.
OTHER INFLAMMATORY MEDIATORS
Other inflammatory mediators travel in the plasma:

Kinins

Coagulation and fibrinolysis proteins

Complement system

C-reactive protein
damaged cells
release
inflammatory
mediators
local
responses
systemic (wholebody) responses
vascular cellular white blood
stage
stage cell response
acute-phase
response
ACUTE-PHASE RESPONSE

Leukocytes release interleukins and tumor
necrosis factor
 Affect
thermoregulatory center  fever
 Affect central nervous system  lethargy
 Skeletal muscle breakdown

Liver makes fibrinogen and C-reactive protein
 Facilitate
clotting
 Bind to pathogens
 Moderate inflammatory responses
FEVER
QUESTION
Tell whether the following statement is true or
false:
Body temperature is controlled through negative
feedback loops.
ANSWER
True
When the body senses a change out of the norm
(as illustrated in the previous slides), it
activates mechanisms that oppose that change
(vasodilation and sweating with increased
temperatures; vasoconstriction and shivering
with decreased temperatures). This is known
as negative feedback. Positive feedback, on
the other hand, senses a change but activates
a mechanism that exaggerates the change.
SCENARIO:
Mr. X says he has “chills and fever”…

His daughter wants you to explain how he could have both
at the same time and from the same disease
Question:

Should she be keeping him warmer or
helping him cool off?
WHITE BLOOD CELL RESPONSE

Inflammatory mediators cause WBC production

WBC count rises

Immature neutrophils (bands) released into blood
CHRONIC INFLAMMATION

Macrophages accumulate in the damaged
area and keep releasing inflammatory
mediators.

Nonspecific chronic inflammation


Fibroblasts proliferate

Scar tissue forms
Granulomatous inflammation

Macrophages mass together around foreign bodies

Connective tissue surrounds and isolates the mass
SCENARIO:

A man had tuberculosis (TB) long ago, and when he first
had the disease, he had a fever, productive cough, and
bloody sputum.

Later, he had trouble breathing and the doctor said his
lungs were “consolidated” with fibrous proteins.

He recovered and his fever went down; he thought he was
cured.

Three years later, an x-ray showed nodules in his lungs and
he was told they contained the TB bacteria.
Question:

Identify inflammatory events in his case.
TISSUE REPAIR
Growth factors stimulate local cells to divide.
 Tissue organization is controlled by the
extracellular matrix.
 New cells are laid down on the extracellular
matrix.

 Tissue
regeneration: injured tissue is replaced by
the same kind of cells
 Fibrous tissue repair: injured tissue is replaced by
connective tissue
º
Granulation tissue  scar tissue
QUESTION
Tell whether the following statement is true or
false:
If you get a paper cut, epithelial tissue will be
replaced with connective tissue.
ANSWER
False
The surface epithelial cells of the skin are most
likely to be damaged in this instance. Surface
epithelial tissue has the ability to regenerate,
replacing the damaged tissue with the same
type (epithelial).
WOUND HEALING

Inflammatory phase

Proliferative phase

Remodeling phase
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