Indirect Induction of Vascular Damage by X-Irradiation

Abstract

The changes in petechial susceptibility of the vessels of hamster cheek to the moccasin venom test have been compared in shielded and irradiated pouches of the same animal which had received median lethal doses of x-irradiation. There was no statistically significant difference demonstrable between the irradiated and controlled cheek pouches, but both showed a greater hemorrhagic response than was found in the cheek pouches of unirradiated control animals. Similar results were found when the diffusion of intradermally injected Evans blue was used as an indication of x-irradiation damage. The shielded and the exposed areas both showed enhanced permeability to the dye when compared with the unirradiated control animals. These results suggest that some indirect factor or factors are involved in the vascular and permeability changes following exposure to ionizing radiation.