Radiation induced alterations in rabbit aortic prostacyclin formation.

Earlier studies have demonstrated very severe vascular lesions occuring after irradiation in human and experimental animals as well. We examined the rabbit aortic PGI2-formation using the platelet bioassay technique in one year aged rabbits after different irradiation doses and a time course. The findings demonstrate a significant increase in prostacyclin formation, which might be due to the damage of endothelial cells. This stage is followed by a long lasting severe depression. This behaviour in addition demonstrates a dose dependent manner, The findings of a long lasting decrease in vascular PGI2-formation might contribute to the understanding of the high incidence of vascular lesions being found at the site of irradiation.