Radiosensitivity of capillary endothelium

作者：H. S. Reinhold, G. H. Buisman · 发表于：British Journal of Radiology · 年份：1973 · DOI：10.1259/0007-1285-46-541-54 · 被引用次数：159 · 研究领域：Effects of Radiation Exposure、Spaceflight effects on biology、Thermoregulation and physiological responses

Starting with a subcutaneous air pouch in the rat, a system was developed in which a thin sheet of connecting tissue was partially separated from its surroundings. In a small area that was depleted of blood vessels by freezing, vascular proliferation was induced by the application of a stimulus employing uric acid and lithium lactate. In unirradiated preparations, the depleted area becomes increasingly re-vascularized in 12 days, while in the irradiated preparations there is a paucity of vessels, the degree of reduction depending on the dose of radiation. As a quantitative indication of the “vascular index” the local amount of an intravenously injected tracer was determined. The tracer substance is a fluorescent dye, and quantification was performed by means of a microfluoro-meter. The “vascular index”, as measured by means of microfluorometry, is probably closest to the vascular silhouette. The “survival curve” derived in this way shows a D0 value of about 170 rads, a N value of about 7, and a DQ of about 340 rads. Split-dose experiments with an initial dose of 500 rads, followed after 24 hours by a test-dose, showed a (D2–D1) value of about 290 rads. In contrast to earlier observations, these results seem to indicate that the radiosensitivity of the endothelial cells of capillaries is of the same order of magnitude as that of epithelial cells and cells of supporting tissues.