[Reactivation of the allogenous component of experimental skin inflammation after exposure to ultraviolet rays]

The effects of U.V. radiation induced cutaneous erythema on an experimental inflammation focus in another part of the body have been studied. The skin inflammation caused by carbon dioxide snow was used as a model. The onset of erythema is followed by reactivation of the diminishing inflammation process. It is therefore deduced that such effects are transmitted humorally and that reactivation is caused by histamine circulation. Histamine is released locally from the U.V. induced erythema and, entering into the circulation, increased the permeability of the microvessels in the inflamed area. This sends inactive chemical mediators to the interstitial sector where the appropriate conditions for their activation exist.