Animal model of vascular inflammation.

Inflammatory mechanisms play a central role in the pathology of a variety of conditions ranging from atherosclerosis, arthritis, cancer and Alzheimer's disease. Under normal conditions the inflammatory response initiates protective actions, but triggers tissue damage under pathological conditions. Acute or chronic inflammation is mediated by nascent expression of a host of proteins such as the cytokines interleukins (IL), tumor necrosis factor (TNF), and interferons. Currently available in vitro or in vivo methods do not offer the specificity to probe the complex inflammatory cascade. We developed an animal model in which a single injection of the proinflammatory cytokines TNF-alpha and IL-1 beta in live rodents initiates a rapid inflammatory reaction which can be monitored by video microscopy and electron microscopy. This model exhibits the characteristic feature of inflammatory reaction such as adhesion and transmigration of leukocytes, and activation and degranulation of platelets and mast cells. This model is applicable to inflammatory processes in the peripheral and cerebral vasculature including the blood-brain barrier disruption in Alzheimer's disease. The animal model of inflammation reported here may prove to be a valuable tool in investigating the pathophysiology of a number of inflammatory diseases and identifying potential targets as well as agents for therapy.