Tsujii H, Irie G
Radiat Med. 1983 Oct-Dec;1(4):320-5.
The early effects of radiation on the local blood flow in the skin of mice were evaluated by measuring the local clearance rate of 133Xe after its subcutaneous injection; this was done at four to five weeks after irradiation during the animals' normal resting conditions. The fractionation schedules employed were single fractions, two fractions in 15 days and four fractions in 15 days. The dose effect curves with these schedules showed a two-component pattern. There was a uniform reduction in flood flow after 10 to 30 Gy, and a steady increase in flood flow after doses more than 40 Gy. The blood flow after higher-fractionated doses was always lower than after less-fractionated doses. It was considered that radiation doses causing higher severity of acute skin reactions might have predominated a degree of acute vasodilatation over fibrotic changes, thus resulting in increased blood flow. A steady increase in early blood flow was observed with increasing severity of acute skin reactions, but the early blood flow was not a good indicator for predicting late skin reactions, except for a severe leg deformity which was accompanied with a significant increase in early blood flow.
通过测量皮下注射133Xe后的局部清除率，评估了辐射对小鼠皮肤局部血流的早期影响；这是在照射后四到五周，动物处于正常休息状态时进行的。采用的分次照射方案为单次照射、15天内分两次照射和15天内分四次照射。这些方案的剂量效应曲线呈现出双组分模式。10至30 Gy后血流量均匀减少，剂量超过40 Gy后血流量持续增加。分次剂量较高后的血流量总是低于分次剂量较低后的血流量。据认为，导致急性皮肤反应更严重的辐射剂量可能在一定程度上使急性血管扩张超过纤维化改变，从而导致血流量增加。随着急性皮肤反应严重程度的增加，早期血流量持续增加，但早期血流量并不是预测晚期皮肤反应的良好指标，除了伴有早期血流量显著增加的严重腿部畸形。
