Inflammation

Question 1

Name some situations in which inflammation can be harmful.

Answer 1

1. Mechanisms used to destroy foreign invaders and necrotic tissue can injure normal tissue.
2. Inflammation can be directed against self-tissues, e.g. autoimmunity and hypersensitivity reactions
3. If the inflammation is not adequately controlled, there can be damage to normal tissue.

Question 2

What are the three major components of inflammation?

Answer 2

1. Alterations is vascular caliber (increased blood flow)
2. Structural changes in microvasculature that allows leukocyte a and plasma proteins to leave circulation, extravasion, and extra vascular deposition
3. Emigration, accumulation and activation of leukocyte a

Question 3

What are the cardinal signs of inflammation (think Roman)?

Answer 3

1. Calor-heat
2. Rubor-redness
3. Tumor-swelling
4. Dolor-pain
5. Functio laesa-loss of function

Question 4

Name four types of stimuli that can activate acute inflammation.

Answer 4

1. Infections (bacterial, viral, fungal, parasitic)
2. Tissue necrosis (ischemia/reperfusion, trauma, physical (burns) and chemical)
3. Foreign bodies (splinter, dirt, sutures)
4. Hypersensitivity (immune reactions, e.g. bug bites, peanuts, autoimmune)

Question 5

Define: Inflammation

Answer 5

Protective response in vascularized connective tissues intended to eliminate the initial cause of injury and remove necrotic debris due to injury.

Question 6

Describe the general chain of events for inflammation.

Answer 6

The stimulus for the injury stimulates the release of soluable chemical mediators from plasma or cells in the connective tissues. The mediators stimulate vascular changes and cellular responses aimed at removing the initial injury stimulus. If the injury stimulus is successfully removed, the continued release of inflammation promoting signals will be inhibited and present leukocyte a will undergo apoptosis. The job is complete and the inflammation response is stopped.

Question 7

Define: Acute Inflammation

Answer 7

Early response type of inflammation where leukocyte e rush to an area to remove the injury stimulus.

Question 8

Name the three principle components of inflammation.

Answer 8

1. Plasma proteins
2. Circulating leukocytes
3. Phagocytes derived from circulating cells

Question 9

What are the three main manifestations at a site of acute injury?

Answer 9

1. Vasodilation
2. Increased vascular permeability
3. Delivery of leukocytes

Question 10

What are the three main steps of recruitment required to get leukocytes to the site of injury?

Answer 10

1. Within the vessel lumen: margination, rolling, and adhesion. Vascular endothelium in its normal inactivated state does not bind circulating cells. During inflammation endothelium is activated and can bind leukocytes.
2. Migration across the endothelium and vessel wall.
3. Migration in tissues toward a chemo tactic stimulus.