1,25-二羟基维生素D3对致死剂量脂多糖攻击的大鼠CD_4~＋CD_（25）~＋Treg细胞的调节作用

目的：观察不同剂量1,25-二羟基维生素D3（1,25-（OH）2D3）短期应用对大鼠受致死剂量脂多糖（LPS）攻击后的保护作用,并探讨此保护作用是否与1,25-（OH）2D3对CD4＋CD25＋Treg细胞的调节作用有关。方法：将大鼠分成3个剂量组,每组20只。分别给予1,25-（OH）2D3 0.125μg/只、0.25μg/只、1μg/只灌胃,3次/周,共2周。另设对照组给予赋形剂。给药后第15天腹腔注射致死剂量LPS（10mg/kg）,每组10只用于观察96 h内的死亡率;其余10只大鼠注射LPS 6 h后抽取外周血并留取脾脏标本。流式细胞仪检测大鼠外周血及脾脏CD4＋CD25＋Treg细胞数量,实时定量PCR检测脾脏Foxp3mRNA水平,ELISA检测外周血IL-10和TGF-β水平。结果：用1,25-（OH）2D3预处理的各组大鼠死亡率均显著低于对照组,用药各组外周血及脾脏CD4＋CD25＋Treg细胞数量、脾脏Foxp3mRNA表达水平、外周血IL-10及TGF-β水平也显著高于对照组。结论：1,25-（OH）2D3能够有效保护大鼠抵抗致死剂量LPS的攻击,这种保护作用可能与1,25-（OH）2D3上调CD4＋CD25＋Treg细胞的数量和功能有关。

Protective effects of 1,25-(OH)_2D_3 in rats given lethal doses of lipopolysaccharide

Objective: We evaluated the protective effects of 1,25-(OH)2D3 in rats given lethal doses of lipopolysaccharide and investigated whether such protection was related to CD4+CD25+Treg cells.Methods: 80 Inbred male Lewis rats were divided into 4 groups and treated with either 0.125 ug,0.25 ug,l ug of 1,25-(OH)2D3 or vehicle by gavage 3 times a week for 2 weeks.On day15,all rats were given lethal doses of lipopolysaccharide(LPS,10mg/kg,i.p.) and the mortality of 10 rates of each group in were recorded within a ...