Recent investigations of mechanisms of chemically induced skin irritation in laboratory mice.

The time course, dose response, components of inflammation, and involvement of putative mediators of inflammation in irritation induced by different chemicals was compared using a mouse ear swelling technique. Differences in time courses of inflammation produced by the irritants were not solely due to differences in rates of penetration. Changes in blood flow and permeability of vessels were phasic with different numbers of phases induced by different irritants. Effects of antagonist, synthesis, inhibitors, and depleting agents of putative inflammatory mediators on intensity of inflammation varied for different irritants. These studies demonstrate that all chemicals do not produce skin irritation by a common inflammatory pathway.