边缘型维生素A缺乏对幼鼠铁营养状况和免疫功能的影响

Impact of vitamin A deficiency on the ironnutritional status and immune function of young rats

目的研究边缘型维生素A缺乏(MVAD)对幼鼠铁营养状况和免疫功能的影响。方法实验分为正常对照组和MVAD组。正常对照组母鼠和幼鼠均给予维生素A(VA)充足饲料;MVAD组母鼠和幼鼠均给予边缘型维生素A缺乏饲料。待两组幼鼠长至7周龄后,测定血清VA、血清铁(SI)、血清铁蛋白(SF)、血红蛋白(Hb)、肝脏铁(LI)含量。MTT法检测T淋巴细胞增殖功能。LDH释放法检测NK细胞杀伤活性。结果与对照组比较,MVAD幼鼠血清铁水平降低,且MVAD幼鼠肝脏铁含量、血清铁蛋白含量显著降低(P<0.05)。MVAD幼鼠的胸腺及脾脏指数、脾淋巴细胞增殖反应、NK细胞杀伤活性显著低于对照组(P<0.05)。结论MVAD可能通过影响铁吸收、储存、转运,改变幼鼠体内铁的营养状况;大鼠孕期、哺乳期MVAD可能抑制幼鼠的免疫功能。

Objective To observe the effect of marginal vitamin A deficiency （MVAD） on iron status and immunity function in young rats. Methods Rats were divided into control and MVAD group. The rats in control group consisted of 20 young rats were fed with normal diet （Vitamin A 2000μgRE/Kg） and those in MVAD group consisted of 19 young rats were fed with MVAD diet （Vitamin A 150μgRE/Kg）. The levels of serum Vitamin A,iron, ferritin,hemoglobin,iron in the liver of rats were determined 7 weeks after feeding. Spleen cells was separated for in vitro culture and deteminationof the proliferative response to PHA and the activity of NK cells. Results Compared with the control group,the levels of iron, ferritin and splenic iron were decreased in MVAD groups （P〈0.05） . The indexes of thymus and spleen,splenic lymphocyte proliferation response and the activity of NK cells in MVAD group were lower than those in control group （P〈0.05）. Conclusion The nutritional status of MVAD may affect the absorption, storage and transportation of iron in the young rats.The immunity in the young rats might be depressed in case marginal vitamin A deficiency occurred during pregnancy and lactation. Key words： Marginal vitamin A deficiency; Iron status; Cellular immunity; Rats