Inflammation-Acute Inflammation

Question 1

What is the intent of inflammation?

Answer 1

eliminate the initial cause of cell injury and the necrotic cells and tissues resulting from the original insult

Question 2

What is the goal of inflammatory reactions?

Answer 2

Bring cells and molecules of host defense from the blood stream to the site of infection or tissue damage

Question 3

When might pathology be the dominant feature of the inflammatory reaction?

Answer 3

The reaction is very strong, prolonged and/or inappropriate

Question 4

What are the cardinal signs of acute inflammation?

Answer 4

• -Heat and redness (vasodilatation and increased blood flow)
• -Redness (increase in metabolic rate in tissue cells)
• -Swelling (accumulation of exudate and migration of inflammatory cells from vessels to tissues)
• -Pain (increase in pressure due to accumulation of cells and exudate and release of chemicals from damaged tissue cells that stim nerve endings)
• -Loss of function (due to pain, cell and tissue destruction, and effects of vascular disturbances on normal physiologic functions)

Question 5

What are the characteristics of vascular response in relation to acute inflammation?

Answer 5

• -active hyperemia and changes in vessel caliber
• -changes in vessel walls, swelling of the endothelial cells
• -gradual slowing of blood flow leading to thrombosis, sludging, and margination of leukocytes

Question 6

What characteristics are associated with exudation of fluids in acute inflammation?

Answer 6

• -increase in hydrostatic pressure –> increased passive filtration of fluid and electrolytes
• -escape of plasma proteins from inflamed capillaries and venules through gaps between endothelial cells

Question 7

What are the main inflammatory mediators?

Answer 7

Histamines
Kinins
PG and LT
PAF
Complement system
Mediators released by neutrophils
Mediators  released by platelets
Peptides
Microbial products
Cytokines
Chemokines

Question 8

What are the characteristics of histamine?

Answer 8

• -found in granules of mast cells and basophils
• -rapidly acting
• -vasoactive
• -main effects: vasodilation, increase vascular permeability (immediate), contract smooth muscle

Question 9

What are the characteristics of kinins?

Answer 9

• -plasma derived
• -produces by actions of kallikreins
• -biologically active polypeptides
• -most significant: bradykinin
• -main effects: vascular effects, produce pain via axon reflex

Question 10

What are the mediators released by neutrophils?

Answer 10

• -Lysosomal granules-contain proteolytic enzymes important for tissue liquefaction and amplification of inflammation
• -specific granules containing proteins with anti-bac properties, can cause mast cell degranulation

Question 11

What are the mediators released by platelets? When are platelets activated? What helps this?

Answer 11

• -Lysosomal granules- contain proteolytic enzymes and cationic proteins
• -Dense bodies (contain serotonin)
• -activated during blood clotting by platelet activating factor: release granules and synthesize PG

Question 12

What are the characteristics of cytokines? What are some examples?

Answer 12

• -protein mediators produced by local cells
• -induce following tissue insults
• -activate adjacent cells or cells at a distance
• -stim initial producing cell
• -IL-1, TNF-alpha: trigger inflammation, induce increased vascular dilation and permeability, produce proteolytic enzymes