低剂量α粒子辐照对斑马鱼胚胎初级造血分子标记物的影响

为探究低剂量α粒子辐照对斑马鱼初级造血的影响，使用241Am作为α粒子辐照源，对脱绒毛膜后的5 hpf胚胎进行0、0.425、0.85、1.7 mGy的辐照，采用整体原位杂交技术检测了约14 hpf斑马鱼胚胎初级造血分子标记物gata1a和spi1b的表达，采用实时荧光定量PCR技术检测了22 hpf斑马鱼胚胎初级造血分子标记物gata1a和spi1b的相对表达，并采用联大茴香胺染色法检测了48 hpf血红蛋白含量的变化。通过与对照组相比发现，0.425 mGy剂量组的gata1a表达无显著性差异（p>0.05），spi1b表达略有减少（p<0.05），血红蛋白含量显著减少；0.85 mGy剂量组的gata1a和spi1b表达均显著降低（p<0.01），血红蛋白含量明显减少；1.7 mGy剂量组的gata1a和spi1b表达均显著升高（p<0.001），血红蛋白含量显著增加。以上结果表明，剂量小于0.85 mGy的α粒子辐照对初级造血产生了抑制作用，而剂量为1.7 mGy的α粒子辐照诱导了胚胎兴奋效应，即剂量为1.7 mGy 的α粒子辐照对胚胎期斑马鱼初级造血具有促进作用。

Effect of Low-dose α Particle Irradiation on Primitive Hematopoietic Molecular Marker in Zebrafish Embryo

In order to investigate the effect of low-dose α particle irradiation on primitive hematopoiesis in zebrafish embryos, the 5 h post fertilization (hpf) dechorionated zebrafish embryos were irradiated at doses of 0, 0.425, 0.85 and 1.7 mGy, respectively, by using ²⁴¹Am as the α particle irradiation source, the expressions of primitive hematopoietic markersgata1a andspi1b in the about 14 hpf zebrafish embryos were detected by the whole-in-situ hybridization (WISH), and that in the 22 hpf zebrafish embryos were analyzed by the real-time fluorescence quantitative PCR (qRT-PCR), and the variations of hemoglobin contents in the 48 hpf zebrafish embryos were measured by the O-dianisidine dyeing. It is found that for 0.425 mGy irradiation group, the expression ofgata1a doesn’t significantly reduce （p>0.05）, the expression ofspi1b slightly reduces（p<0.05）, and the hemoglobin content slightly decreases. For 0.85 mGy irradiation group, the expressions ofgata1a andspi1b significantly reduce （p<0.01）, and the hemoglobin content also significantly reduces. For 1.7 mGy irradiation group, the expressions ofgata1a andspi1b significantly increase （p<0.001）, and the hemoglobin content also significantly increases. The results show that α particle irradiation at dose of less than 0.85 mGy has an inhibitory effect on primary hematopoiesis in zebrafish embryos, while at dose of 1.7 mGy induces hormesis effect. Therefore, α particle irradiation at dose of 1.7 mGy can promote primitive hematopoiesis in zebrafish embryos.