新生SD大鼠血常规各项与发育时间的相关性分析及其与血清铁浓度变化的机制

 目的：探讨经心脏穿刺和剪尾2种采血方式对新生SD大鼠血常规的影响；建立其血常规正常参考值范围；研究发育过程中血常规各项、血细胞形态和血清铁（SI）的消长变化及其相互关系，揭示SI变化的可能机理。方法：新生鼠出生后1、2、3、7和14 d，经全自动血液分析仪检测心脏血和鼠尾血中红细胞(RBC)计数、血红蛋白(HGB)含量、血小板(PLT)计数和白细胞(WBC)计数的改变；通过瑞氏-姬姆萨染色观察2种血液中血细胞形态的差别，及其在不同发育阶段的变化情况；选择心脏穿刺采血建立血常规正常值参考范围；经血液生化分析仪检测各时点心脏血SI含量变化；统计学分析发育时间、血常规各项及SI含量三者间的动态关系。结果：鼠尾血中RBC计数、HGB含量和WBC计数均高于心脏血，且RBC碎片较多；RBC形态随发育逐渐成熟稳定，其碎片亦明显减少；发育时间与心脏血中RBC和PLT计数呈正相关(P<0.01)，与HGB含量、红细胞压积(HCT)、红细胞平均体积(MCV)、平均血红蛋白量(MCH)、平均血红蛋白浓度(MCHC)、WBC计数和SI含量呈负相关(P<0.01)。SI含量与RBC计数呈负相关(P<0.05)，与MCV(P<0.01)和MCH(P<0.05)则呈显著正相关。结论：经心脏采血能建立相对完善的正常新生SD大鼠血常规参考值范围；新生鼠血常规各项与发育时间存在显著相关性；发育早期RBC的不稳定性可能是导致SI含量在发育早期较高的原因。

Correlation between routine blood indexes and postnatal development and change of serum iron concentration in neonatal SD rats

AIM:To compare the indexes of blood samples collected from the heart and tail in neonatal SD rats for establishing reliable blood index reference in neonatal SD rats, and to determine the developmental changes in blood indexes, blood cell morphology and serum iron (SI) in SD rats. METHODS:Automatic blood cytoanalyzer was used to measure the indexes of blood collected from the heart or tail at postnatal day 1 (P1), P2, P3, P7 and P14. The morphology of the blood cells in the blood smear was observed under microscope. The SI concentration in the cardiac blood was detected by a biochemical analyzer. The correlations between blood indexes and developmental stage or SI concentration were analyzed. RESULTS:Red blood cell (RBC) count in the tail blood was much higher than that in the cardiac blood at P1, P2 (P<0.01) and P14 (P<0.05). Hemoglobin (HGB) and white blood cell (WBC) count in the tail blood were higher than those in the cardiac blood (P<0.01) at all ages tested. The observation of cardiac blood smear showed that RBC volume and RBC debris decreased gradually with the development. RBC count and platelet count increased with the development (both P<0.01), while the levels of HGB, WBC count, hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC) and SI concentration were negatively correlated with age (all P<0.01). SI concentration was positively correlated with MCV (P<0.01) and MCH (P<0.05), but it had a negative correlation with RBC count (P<0.05). CONCLUSION: Cardiac blood provides more reliable blood index reference in neonatal SD rats. Dynamic changes of blood indexes correlate significantly with the development. Immaturity of RBC may be associated with higher SI concentration at early stage of development.