HCT lab module 1.2 Flashcards
A protective response, designed to remove the organism of both the initial cause of cell injury
(e. g. microbes, toxins) and the consequences of such injury (e.g. necrotic cells and
tissues) .
Inflammation
The local response of living mammalian tissues to injury due to any agent that disturb the normal steady state.
inflammation
A dynamic process, evolving through several
phases that last from a few minutes to days or even months and years.
inflammation
Inflammation of sudden onset and short duration
acute inflammation
Inflammation lasts a long time
chronic inflammation
[T or F] Inflammation occurs only in multicellular organisms that are capable of mounting a neuromuscular and cellular response to injury
True
[T or F] Inflammation occurs only in living tissues.
True
[T or F] The inflammatory response is not closely intertwined with the process of repair.
false
4 cardinal signs of inflammation
State both roman and english name:
✓ rubor (redness)
✓ tumor (swelling);
✓ calor (heat); and
✓ dolor (pain)
Who presented the 4 cardinal signs of inflammation? When was it introduced?
Roman writer Celsus in 1st century A.D.
Fifth sign of inflammation added by Virchow
functio laesa (loss of function)
[T or F] The word inflammation means flaming.
False - burning
is of short duration (lasting less than 2weeks) and represents the early body reaction, resolves quickly and is usually followed by healing.
Acute inflammation
is of longer duration and occurs either after the causative agent of acute inflammation persists for
a long time, or the stimulus is such that it induces chronic inflammation from the
beginning.
Chronic Inflammation
the type of chronic inflammation in which
during the course of the disease, there are acute exacerbations of activity.
chronic active inflammation
The three major components of acute inflammation are:
✓ alterations in vascular caliber that lead to an increase in blood flow;
✓ structural changes in the microvasculature that permit plasma proteins and leukocytes to leave the circulation; and
✓ emigration of leukocytes from the microcirculation, their accumulation in the focus of injury, and their activation to eliminate the offending agent
The major manifestations of acute
inflammation, compared to normal.
1 , Vascular dilation and increased blood flow (causing erythema and warmth);
2, extravasation and extravascular deposition of
plasma fluid and proteins(edema);
3, leukocyte emigration and accumulation in the site of injury.
Acute inflammatory response process can be divided into two:
I. Vascular events
II. Cellular events
The earliest response to tissue injury is the alteration in the microvasculature
- alterations include: hemodynamic changes and changes in vascular permeability
Vascular events
earliest features of inflammatory response result from changes in the vascular flow and calibre of small blood vessels in the injured tissue.
Hemodynaic Changes
Progression of hemodynamic changes:
- Transient vasoconstriction
- Persistent progressive vasodilation
- local hydrostatic pressure
- Slowing or stasis
- Leukocyte margination
occur immediately irrespective of the type of
injury. Mild form injury, the blood flow may be reestablished in 3-5 seconds, and in more
severe injury, the vasoconstriction may last for about 5 minutes.
Transient vasoconstriction
involves mainly the arterioles, but to a
lesser extent, affects other components of the microcirculation like venules and
capillaries. This can be seen within half an hour of injury.
- results in increased blood volume, which is responsible for the redness and warmth at the site of acute inflammation.
Persistent progressive vasodilation
results in transudation of fluid into the extracellular space. This is responsible for the swelling at
the local site of acute inflammation.
local hydrostatic pressure
causes increased concentration of
red cells raising blood viscosity.
Slowing or stasis
also known as the peripheral orientation of
leukocytes (mainly neutrophils) along the vascular endothelium.
Leukocyte margination
The leukocytes briefly sticks to the vascular endothelium before moving and migrating through the gaps between the endothelial cells and into extravascular space.
Emigration
In and around the inflamed tissue, there is accumulation of edema fluid in the interstitial
compartment which comes from blood plasma by escaping through the endothelial wall
of the peripheral vascular bed.
Altered Vascular Permeability
Filtrate of blood plasma without changes in
endothelial epermeability
Transudate
Edema of inflamed tissue associated with
increased vascular permeability
Exudate
Characterizes a Non-inflammatory edema
Transudate
Characterizes an inflammatory edema
Exudate
protein content: Low (less than 1g/dL); mainly albumin, low fibrinogen; hence no tendency to coagulate
Transudate
Protein content: High 2.5-3.5 g/dL), readily coagulates due to high content of fibrinogen and other coagulation factors
Exudate
Glucose Content: Same as in plasma
Transudate
Protein content: Low (less than 60 mg/dL)
Exudate
Specific gravity: Low (<1.015)
Transudate
Specific gravity: High (>1.018)
Exudate
pH: >7.3
pH: <7.3
Transudate
Exudate
Few cells, mainly mesothelial cells and
cellular debris
Example is edema in congestive heart failure
Transudate
Many cells, inflammatory as well as
parenchymal
Purulent exudate such as pus
Exudate
[T or F] In acute inflammation, normally non-permeable endothelial layer of the microvasculature becomes leaky
true
The mechanisms of increased vascular permeability are
Hint: 5 mechanisms
- Contraction of endothelial cells (contraction)
- Retraction of endothelial cells (retraction)
- Direct injury to endothelial cells (direct injury)
- Endothelial injury mediated by
leukocytes (Endothelial injury by leukocytes) - Leakiness in neovascularisation (leakiness)
most common mechanism of increased leakiness that affects venules exclusively
while capillaries and arterioles remain unaffected
Contraction of endothelial cells
It is mediated by the release of histamine, bradykinin and other chemical mediators.
Contraction of endothelial cells.
The response begins immediately after injury, usually reversible, and for short duration only
(15-30 minutes).
Contraction of endothelial cells
In this mechanism, there is structural reorganization of the cytoskeleton of endothelial cells that causes reversible retraction at the intercellular junctions.
Retraction of endothelial cells
This change affects venules and is mediated by cytokines like interleukin-1 (IL-1) and tumor necrosis factor (TNF)-α.
Retraction of endothelial cells
The onset of response takes 4-6 hours after injury and lasts for 2-4 hours or more (somewhat delayed and prolonged leakage).
Retraction of endothelial cells