低剂量砷染毒对大鼠游离血红蛋白及CD163的影响

The effect of low concentration of arsenic on free hemoglobin and CD163 in rats

目的观察低剂量砷染毒后大鼠血浆中游离血红蛋白（F—Hb）、分泌型CD63（sCD163）的含量和肝组织中CD163的表达变化，以探究砷中毒对红细胞及吞噬细胞的影响，为慢性砷中毒早期防治的细胞分子机制研究提供依据。方法健康雄性SD大鼠32只，按体质量采用随机数字表法分为对照组、低剂量组、中剂量组、高剂量组，每组8只大鼠。4组大鼠通过自由饮水方式染毒，砷含量依次为0、80、400、2000μg／L。染毒2个月后，腹主动脉采血并留取肝脏组织标本。全自动血细胞分析仪检测红细胞参数；酶联免疫吸附试验（ELISA）检测血浆F—Hb及sCD163的含量：免疫组化方法分析大鼠肝脏中CD163的变化。结果低、中、高剂量组与对照组比较，红细胞各项参数包括红细胞计数、血红蛋白含量、红细胞压积、红细胞平均体积、红细胞平均血红蛋白含量、红细胞平均血红蛋白浓度及红细胞分布宽度差异均无统计学意义（P均〉0．05）；低、中、高剂量组血浆F—Hb[（7．58±1．42）、（7．85±1．61）、（9．52±2．22）mg／L]与sCD163含量[（19．49±2．49）、（17．92±2.32）、（20．02±3．42）mg／L]均高于对照组[（4．34±0．40）、（12．48±1．65）mg／L，P均〈0．05]，且F—Hb与sCD163存在相关性（r=0．74，P〈0．05）；低、中、高剂量组大鼠肝组织中CD163阳性细胞数（9．4％、6．1％、4．5％）少于对照组（25．0％，x^2=12．988，P〈0．05）。结论低剂量砷染毒，可以导致大鼠外周血F—Hb含量和sCD163表达升高。这种变化一定程度上反映大鼠发生了红细胞损伤和伴随的炎性改变。同时，具有吞噬和清除功能的CD163阳性活化巨噬细胞的减少可能与砷性肝损伤有关。

Objective To study the contents of plasma free hemoglobin （F-Hb） and sCD163 and expression of CD163 in liver in order to explore the impact of red blood cells and phagocytes, and to provide a basis for cellular and molecular mechanism study in order to carry out early prevention and treatment of chronic arsenic poisoning. Methods Thirty-two male Sprague-Dawley rats were divided into 4 groups according to their body weight via a random number table method, 8 rats in each group： control group, 80μg/L As treatment group, 400 μg/L As treatment group and 2 000 μg/L As treatment group. Animals were infected with sodium arsenite through drinking water. Blood samples were obtained from abdominal aorta after As treatment, and samples of liver tissues were harvested. Erythrocyte parameters were measured with automated blood analyzer, the levels of F-Hb and sCD163 were determined by enzyme-linked immunosorbent assay （ELISA）; CD163 in rat liver was analyzed via immunohistochemical method. Results No significant change was found in red blood cell parameters between groups （all P 〉 0.05）. The contents of F-Hb [（7.58 ±1.42）, （7.85 ±1.61）, （9.52± 2.22） mg/L] and sCD163 [（19.49 ± 2.49）, （17.92 ±2.32）, （20.02 ±3.42） mg/L] in arsenic infected group were significantly higher than those of control group [（4.34 ±0.40）, （12.48 ±1.65） mg/L], the differences were statistically significant （all P 〈 0.05）, and there was a certain correlation between F-Hb and sCD163 （r = 0.74, P 〈 0.05）. The numbers of CD163 positive cells in arsenic infected group （9.4%, 6.1%, 4.5%） decreased compared with that of control group （25.0%, X2 = 12.988, P 〈 0.05）. Conclusions The increased levels of F-Hb and sCD163 under low levels of arsenic exposure can reflect the damage degree of red blood cells and the level of inflammation; at the same time, the number of CD163 positive maerophage that can ingest foreign particles is reduced, which may be related to the damage degree of liver in rats exposed to arsenic.