Effects of phytate feeding and Zn deficiency on phytase activities of intestinal mucosa.

饲喂植酸和缺锌对肠粘膜植酸酶活性的影响。

• 批准号: 05680046
• 负责人: SHINODA Shoko
• 金额: $ 1.22万
• 依托单位: Tachikawa College of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05680046/
• 关键词: Sodium phytate; Rat; Intestinal phytase; Zn defficiency; Alkaline phosphatase; フィチン酸; 小腸; フィターゼ; Zn欠乏

The lowering of phytase activities of intestinal mucosa is observed when phytate is fed to rats. This may be caused by inhibitory effect of dietary phytate to zinc absorption in intestinal tract. Therefore, effects of phytate feeding and zinc deficiency on intestinal phytase activity was studied.Phytate containing diets (1% or 2%) or zinc deficient diets (zinc : 3 mu g / kg of diet) were fed to the thirty growing male rats. Thus, zinc contents of femur of rats were significantly decreased by both phytate-containing and zinc deficient diets after three weeks of feeding. Mucosal homogenate were prepared from the upper part (1/3) of small intestine for measurement of enzyme activities.In this experiments, mucosal phytase activity was decreased by phytate-feeding, but not by zinc deficiency. Zinc contents of mucosal homogenate were 0.241 mu g / mg protein for the control diet, and 0.214-0.286 mu g / mg protein for phytate-containing and zinc deficient diets. There was not obvious different in the amount of zinc in intestinal mucosa. Alkaline phosphatase activities, which known as zinc enzyme, were also measured for same mucosal homogenate. There was no significant difference among the experimental diets. Therefore, it is clear that the decreased intestinal phytase activities by phytate feeding is not caused by zinc deficiency which effected by phytate, inhibitor for mineral absorption.

给大鼠喂饲植酸盐可使肠粘膜植酸酶活性降低。这可能是由于植酸盐抑制了锌在肠道的吸收。因此，研究了植酸饲料和缺锌对肠道植酸酶活性的影响，给30只生长期雄性大鼠喂食含植酸饲料（1%或2%）或缺锌饲料（锌：3 μ g / kg饲料）。因此，三周后，含植酸盐和缺锌饮食的大鼠股骨锌含量显着下降。从小肠上部（1/3）制备粘膜匀浆，测定小肠粘膜植酸酶活性，结果表明，饲以植酸盐可降低小肠粘膜植酸酶活性，但缺锌对小肠粘膜植酸酶活性无影响。对照组胃粘膜匀浆锌含量为0.241 μ g / mg蛋白质，含植酸和缺锌组胃粘膜匀浆锌含量为0.214-0.286 μ g / mg蛋白质。肠粘膜锌含量无明显差异。碱性磷酸酶的活性，这被称为锌酶，也被测量为相同的粘膜匀浆。试验日粮间无显著差异。因此，植酸盐引起的肠道植酸酶活性降低不是由于锌缺乏引起的，而锌缺乏是由于植酸盐这种矿物质吸收抑制剂的影响。