Inflammation

Inflammation is a protective mechanism against injury or infection, including mechanical damage, oxygen deprivation (ischemia), genetic or immune defects, chemical agents, temperature extremes, or ionizing radiation. It helps eliminate the initial cause of injury, removes damaged cells and tissues from the original insult, and initiates tissue healing and repair. Restoration of the injured tissue to its original form and function depends on the extent of the damage. Without inflammation, an infection would not be controlled, and a wound would not heal, leading to detrimental consequences. Simultaneously, too much inflammation could have harmful implications such as the development of chronic conditions including atherosclerosis (buildup of plaque in the blood vessel wall) and cancer due to the production of harmful agents. The chapter defines inflammation, and describes how it is triggered. It goes on to list the cell types associated with inflammation and the roles played by them, and then the chemical mediators associated with inflammation and the specific roles played by them. The chapter identifies the different forms of inflammation, and summarizes its key characteristics. It describes the cascade that is turned on once acute inflammation is triggered, and names the most common antiinflammatory agents and their means of reducing inflammation.