RS_3对大鼠微量元素铁、锰吸收的影响

Effect of RS_3 on the Absorption of Iron and Manganese Trace Elements in Rats

本文研究了RS_3抗性淀粉对大鼠微量元素铁和锰吸收的影响。将32只Wistar雄性大鼠随机分为4组,对照组、20%RS_3组、40%RS_3组和60%RS_3组,饲料分别为基础饲料中的0%、20%、40%和60%淀粉由RS_3替代,试验期35 d。采用火焰原子吸收光谱法测定饲料、粪便、血清、肝、毛、回肠内容物和盲肠内容物中铁、锰含量,计算表观吸收率。结果显示:40%RS_3组和60%RS_3组的铁表观吸收率高于对照组(p<0.05),40%RS_3组和60%RS_3组肝中铁含量高于对照组(p<0.01),对照组和实验组的血清、毛中铁的含量差异无统计学意义(p>0.05),40%RS_3组和60%RS_3组盲肠内容物重量,及其中可溶性Fe、可溶性Fe/总Fe高于对照组和20%RS_3组(p<0.05)。随RS_3摄入量增加锰表观吸收率、回肠和盲肠内容物可溶性Mn、可溶性Mn/总Mn增大,但差异无统计学意义。结果表明,RS_3增大了回肠和盲肠中铁的溶解度,提高了大鼠对铁的吸收;RS_3对大鼠Mn的吸收可能有促进作用。

The effect of RS3-resistant starch on the absorption of iron and manganese in rats was studied. Thirty-two male Wistar rats were randomly divided into four groups： the control group, 20%-RS3 group, 40%-RS3 group, and 60%-RS3 group. The starch in the basic feed was replaced by 0%, 20%, 40%, and 60% RS3, respectively. The duration of the testing period was 35 days. The amounts of iron and manganese in the feed, feces, serum, liver, hair, ileum content, and cecum content were determined by flame atomic absorption spectrophotometer and the apparent absorption was calculated. The results revealed that the apparent absorption rate of iron in the 40%-RS3 and 60%-RS3 groups was higher than that in the control group（p〈0.05）. The iron content in the liver of the 40%-RS3 and 60%-RS3 groups was also higher than that in the control group（p〈0.01）. No significant difference was found in the amounts of iron in the serum and hair between the control group and experimental groups（p〉0.05）. The amount of soluble iron and the ratio of soluble iron/total iron in the ileum and cecum contents of the 40%-RS3 and 60%-RS3 groups were higher than that in the control group（p〈0.05）. With the increase of RS3 intake, the apparent absorption rate of manganese, soluble manganese, and the ratio of soluble manganese/total manganese in the ileum and cecum contents was found to increase, but the difference was not statistically significant. This study demonstrated that RS3 increased the solubility of iron in the ileum and cecum and effectively improved the absorption of iron. RS3 might also promote the absorption of manganese in rats.