The Action of Radium on Blood Supply: The White Reaction

Abstract

After a surface application of radium the skin sometimes show a white or pale area corresponding to the part radiated. This precedes the erythema and is usually accompanied by slight œdema. When the thin, transparent, featherless skin overlying the pectoral muscle in the chicken is radiated with β radiation, a white discoloration appears in the underlying muscle two or three days later, and may persist until it is concealed by the onset of erythema in the overlying skin. This white reaction also occurs in tumours when they are radiated, a previously described.1 If a mouse or a new-born rat be inoculated subcutaneously with a small piece of tumour, the subcutaneous growth which arises appears pink through the translucent skin. If this tumour be radiated with β or γ radiation it will turn purple in a few days and subsequently white and bloodless. If it has been given a dose of radiation sufficient to cause it to disappear, then it will remain white or yellowish. If however, a sub-lethal dose has been given, then its normal pink colour will return and it will continue to grow. In old rats it is not possible to see these vascular changes on account of the opacity of the skin. They can, however, be demonstrated by inoculating large quantities of Indian ink into the tail vein.