Acute and Chronic Inflammation

Question 1

What are the cardinal signs of inflammation?

Answer 1

rubor (redness)

calor (heat)

tumor (swelling)

dolor (pain)

loss of function

Question 2

What is erythema?

What could have caused it?

Answer 2

superficial reddening of the skin as a result of inflammation

contact with an irritant chemical, prolonged sun exposure

Question 3

What is the simplest indicator of acute inflammation?

Answer 3

increase in white blood cell count in the peripheral blood

Question 4

What are vascular changes in the process of inflammation?

Answer 4

vasodilation - increase blood flow

vascular permeaility

increased adhesion of white blood cells

stasis and concentration of RBC’s

Question 5

What is the purpose of vascular stasis?

Answer 5

slowing of the blood in the blood stream allows chemical mediators and inflammatory cells to respond to the stimulus

Question 6

What chemical mediators promote vasodilation?

Answer 6

histamine, prostaglandins and NO

Question 7

What are PAMP’s?

What do they do?

Answer 7

pathogen-associated molecular patterns

bind to pattern recognition receptors (PRRs) on macrophages which causes the macrophage to release inflammatory mediators

Question 8

What is diapedesis?

Answer 8

movement of leukocytes out of the circulatory system towards the site of tissue damage or infection

Question 9

What causes endothelial cells near the site of infection to express cellular adhesion molecules?

Answer 9

release of cytokines by macrophages at the site of inflammation

Question 10

What is the first step of leukocyte extravasation (diapedesis)?

CAPTURE

Answer 10

selectin ligand (PSGL-1) on leukocyte cell surface binds to P selectin on endothelial cell

Question 11

What are the five steps of the leukocyte adhesion cascade?

Answer 11

capture

rolling

slow rolling

firm adhesion

transmigration

Question 12

What happens during ROLLING?

Answer 12

bonds between P-selectin and PSGL-1 are formed at the leading edge and broken at the trailing edge

Question 13

What must be present for a leukocyte to migrate across resting endothelium?

Answer 13

chemoattractants

Question 14

What are three causes of chronic inflammation?

Answer 14

persistant infection

prolonged exposure to potentially toxic agents

autoimmunity (rheumatoid arthritis, MS)

Question 15

What is autoimmunity?

Answer 15

inappropriate inflammatory response when there are no foreign substances to fight off

Question 16

Describe the cellular events of acute inflammation?

Answer 16

cellular recruitment and activation of neutrophils (polymorphonuclear leukocytes)

Question 17

What causes rubor and calor?

Answer 17

vasodilation

the increased blood flow causes redness and warmth

Question 18

What causes tumor?

Answer 18

increased permeability leading to exudation of protein rich fluid into the extravascular space

Question 19

How do blood vessels alter their permeability?

Answer 19

endothelial cells contract, widening intercellular gaps

Question 20

How does colloid osmotic pressure change after inflammation?

Answer 20

decreases because after vascular permeability has been altered as a response to acute inflammation a protein rich fluid (exudate) leaks out

Question 21

What are the possible outcomes of acute inflammation?

Answer 21

progresses to chronic inflammation

normal function

pus formation

healing leading to fibrosis and loss of normal function

Question 22

What chemical mediators are preformed (within secretory granules)?

Answer 22

histamine - mast cells, basophils and platelets

serotonin - platelets

lysosomal enzymes - neutrophils, macrophages

Question 23

What are macrophages called in the blood?

Answer 23

monocytes

Question 24

Where do T lymphocytes mature?

Answer 24

thymus gland

Question 25

What do integrin receptors on a neutrophil bind to on the endothelium?

Answer 25

immunoglobin superfamily