chapter 2 inflammation Flashcards
what are the two causes of desease
congenital and acquired
congenital
inherited, Intrauterine Lesions- malformation
acquired
Inflammation – Neoplasia (cancer) – Immunologic (rhematoid arthritis) – Vascular (heart 0failure, heart attack – Endocrine (afrenal galnd) – Degeneration (alzheimers disease) – Iatrogenic (caused by the health care provider- example didn't wash hands properly)
what causes inflammation
Infection – Chemical Agents – Physical Agents (Radiation, Heat, Cold) – Trauma – Chronic Irritation
what is he difference btw acute and chronic inflamation
Inflammation of sudden onset and short
duration is characterized as acute, in contrast to
chronic inflammation, which lasts a long time
what is inflammation
Response of living tissue to irritation or injury
Inflammation occurs only in multicellular
organisms capable of mounting a
neurovascular and cellular response to injury
• In contrast to cell injury, which occurs at the
level of single cells, inflammation is a
coordinate reaction of the animal and human
body, and it involves nerves, vessels, blood
cells, and soluble mediators of inflammation
what is inflammations role
protective role, Some times the process may become
uncontrollable, producing more harm than
good. For example, pulmonary tuberculosis
elicits a protective tissue reaction. This
inflammatory response may erode pulmonary
vessels and cause massive bleeding
what are some side effects of inflammation
noxious. For example, fever, which initially
has a beneficial effect, may be so high that it
may cause death
can a gangrenous foot become inflammed
no because Inflammation occurs only in living
tissues
• Necrotic or dead tissue cannot
mount an inflammatory response.
what are the signs of inflammation
exam q: calor (heat) • rubor (redness) • tumor (swelling) • dolor (pain) • functio laesa or disturbed function, as the classical symptom
what is the bodies first response to blood flow
Hemodynamic (vascular) changes - change in blood flow represent the body’s first response
injury.
– The redness and swelling of the skin following a slap
on the face or spanking are typical examples of such a vascular response
what does an increase in blood flow do to regulate hemodynamic chages
The mechanic stimulus (ex. hand) stimulates nerves that
transmit signals to smooth muscle cells on precapillary arterioles. The smooth muscle cells
act as sphincters, regulating the inflow of blood into the capillaries
what is the first response of arterioles to an injurious stimulus, what is the second
vasoconstriction,
which lasts only a few seconds
• This is followed by vasodilatation (ie.,
relaxation of the precapillary sphincter), which results in flooding of
the capillary network with arterial
blood, manifested by redness and mild
swelling of the tissue engorged by blood
what is hyperemia
• Increased blood flow to capillaries (Vasodilatation) → Hyperemia – Red – Swelling → Pain – Heat – → Congestion The blood flow in dilated capillaries and venules is slow, which leads to congestion (the Latin root of which means “heaping together”)
what do rbc do in inflammation
Sludge & form rouleaux (stacks like
coins) - delay circulation further
what do wbc do in inflammation
are marginalized & attached to
endothelium (pavementing)
where are surface adhesion molecules found
e normally present on leukocytes and endothelial cells
what is the role of interleukins
soluble mediators of inflammation- which activates surface components of cells
what initiates clotting
Platelets adhere to endothelium-
The permeability of the vessel wall of
capillaries and postcapillary venules changes in response to inflammation as:
Increased pressure inside the congested blood vessels
• Slowing of the circulation, which reduces the
supply of oxygen and nutrients to endothelial
cells
• Adhesion of leukocytes and platelets to
endothelial cells
• The release of soluble mediators of
inflammation from inflammatory cells,
platelets, endothelial cells, and plasma
what two classes of substances do the mediators of inflammation belong to
plasma-derived
and
cell-derived
how do plasma-derived mediators circulate
in an inactive form and must be
transformed into an active form by an activator. There are numerous specific
and non-specific activators
how do cell-derived mediators mediate
Cell-derived mediators may be preformed and stored in granules of platelets and leukocytes, or they may be
synthesized de novo on demand.
what is an example of a preformed mediator
histamine( from Platelets & Mast Cells)
what is an example of a slower mediator
bradykinin Protein formed in plasma from
Hageman activation)
what is histamine
: Early in inflammation, the vessels become leaky because of the action of biogenic amines, like histamine, and inflammatory
polypeptides, like bradykinin
what is bradykinin
A plasma protein formed through the action of the enzyme kallikrein on a precursor kininogen. It has effects similar to those of
histamine, but at a slower pace (in Greek, bradys means slow, and kinein means acting)
what does the activation of haegeman factor lead to
to increased
vascular permeability, clotting and thrombolysis
what are complemental cascades
another important source of mediators of inflammatoin 9 different proteins
how can the complement cascades be activated
through two pathways:
– Classical
– Alternate
what is the classcal pathway
typically activated by antigenantibody
complexes formed in immune reactions. It can
also be initiated by some proteolytic enzymes,
what is the alternate pathway
activated by bacterial endotoxins,
fungi, snake venom, and some other substances.
what is the MAC
membrane attack complexe • Both pathways converge toward a common
terminal pathway, which finally leads to the
formation of the membrane attack complex
(MAC)
• The MAC is enzymatically active and is able to
destroy cells by literally boring holes in
membranes
WHAT ARE Arachidonic Acid Derivatives
An important group of mediators of inflammation: • Derived from the phospholipids of cell membranes through the action of phospholipase. splits into 2 metabolic pathways
what are the 2 ways that arachidonic acid derivitaives that are already formed be further metabolized
The lipoxygenase pathway
– The cyclooxygenase pathway
whatis the lipoxygenase pathway
The lipoxygenase pathway leads to the
formation of leukotrienes, which are active in
chemotaxis , increase vascular permeability,
also known as the slow-reacting substances of
anaphylaxis (SRS-A), and they cause
bronchospasm in asthma and anaphylactic
shock by contracting the smooth muscles in
the bronchi
what is the cyclooxygenase pathway
leads to
formation of the prostaglandins, prostacyclin
and thromboxane, which cause vasodilatation.
Thromboxane promotes platelet aggregation
and thrombosis, whereas prostacyclin
counteracts this effect
what are the two major cellular events in inflammation
Emigration of Leukocytes
and Phagocytosis
what is transudation
leakage of fluid from the
vessels into the interstitial spaces
what is edema and how does it form
-transudation accounts
for the formation of edema, rich in protein, but contains few cells
how is exudate formed
Emigration, or diapedesis, of cells across the vascular wall
leads to the formation of exudate which contains much
more protein than transudate and inflammatory cells.
what is Emigration, or diapedesis
is the movement of leukocytes out of the circulatory system and towards the site of tissue damage or infection
during emigration or diapedesis of an acute inflammation what type of cells are they
polymorphonuclear leukocytes, also called polymorphonuclear neutrophils (PMNs)
• Increased permeability → leakage of
fluid (transudation) → edema fluid
remember
• Emigration of cells out of vessel →
exudate (Mainly PMNs)
(PMN = Polymorphonuclear Leukocyte)
remember
what becomes apparent in the exudate within the
first 48 hours
• As the inflammation evolves, PMNs are joined by
other cells, such as monocytes and eosinophils
