中文摘要：

目的探讨不同剂量电离辐射全身照射对免疫细胞中PKCθ表达的影响。方法用免疫细胞化学ABC法观察了小鼠胸腺和脾细胞中PKCθ的表达变化。结果低剂量电离辐射和高剂量电离辐射均能增强胸腺和脾细胞PKCθ分子在胞浆中的表达和膜转位，在胸腺中呈现明显的剂量依赖性。结论在电离辐射作用下，PKCθ表达上调、膜转位增强，它不仅参与T细胞的成熟与活化过程，可能同时参与其他信号传导而具有多种生物活性，但它是电离辐射影响机体免疫功能的重要因素之一。

英文摘要：

Objective To observe the effect of ionizing radiation on protein kinase Cθ （PKCθ） expression in immune cells from thymus and spleen in mice. Methods Avidin-biotin-complex was used to detect the cytoplasm-expression and membrane-translncation of PKCθ in the splenocytes and thymoeytes at 24 h after the whole body irradiation （WBI） with different doses of X-rays. Results The results showed that both low dose radiation and high dose radiation caused significant up-regulation of PKCθ in the cytoplasm and on the membrane of splenocytes and thymocytes （P 〈 0.05 or P 〈 0.01 ）, both of which were more significant and dose- dependent in the thymocytes. The cytoplasm expression of PKCθ in the thymocytes peaks with 2 Gy irradiation and that in the splenocytes has not attained to the significant acme during the whole course, but with higher expression in both organs than those in control. The ratio of PKCθ membrane-positive cells in the thymus begins to rise dose-dependently from 0.1 Gy, peaks at 2 Gy and then descends until 10 Gy; that in the spleen is much higher than that in the thymus within the range of 0.075-0.5 Gy, but much lower within 0.5-10 Gy. Conclusions Ionizing radiation can induce the expression of PKCθ up-regulated significantly in the cytoplasm and on the membrane, which shows that PKCθ not only participates the maturation and activation of T cells, but also plays a role in other signal transduetions at the same time and so has multiple biological activities. It is one of the key factors that make ionizing radiation affect the immunological function of organisms.