Sampson D A, Harrison S C, Clarke S D, Yan X
Department of Food Science and Human Nutrition, Colorado State University, Fort Collins 80523, USA.
J Nutr. 1995 Aug;125(8):2199-207. doi: 10.1093/jn/125.8.2199.
Weanling male rats were fed diets that varied in protein quality (casein or wheat gluten) and vitamin B-6 (0.0, 0.5, 1.0 and 1.5 mg pyridoxine HCl/kg diet) to test the hypotheses that low protein quality would depress vitamin B-6 nutritional status and that activity of ornithine decarboxylase (ODC) would be a sensitive functional indicator of vitamin B-6 nutritional status. The wheat gluten diet depressed body weight gain approximately 17% at higher vitamin B-6 levels, as expected. However, vitamin B-6 nutritional status was not worse in gluten-fed compared with casein-fed groups, as evidenced by static measures (B-6 vitamer concentrations in plasma and tissues) and a functional indicator (tryptophan load test). The activity of ODC (holo- and total) in liver, kidney and small intestine did not vary significantly at the three higher levels of vitamin B-6 intake. In groups fed casein, total ODC activity in these tissues was two- to fivefold higher in rats fed diets containing 0.0 mg vitamin B-6/kg compared with higher B-6 levels, without corresponding differences in ODC mRNA abundance in liver and kidney. Concentrations of B-6 vitamers (except pyridoxal phosphate in plasma) increased linearly with dietary vitamin B-6 in plasma, liver, kidney and intestine. These data suggest that low quality protein fed as wheat gluten suppresses growth but not vitamin B-6 nutritional status, and that ODC activity is not a sensitive functional indicator of marginal vitamin B-6 status.
给断乳雄性大鼠喂食蛋白质质量（酪蛋白或小麦麸质）和维生素B - 6含量（0.0、0.5、1.0和1.5毫克盐酸吡哆醇/千克饲料）不同的饲料，以检验以下假设：低质量蛋白质会降低维生素B - 6营养状况，鸟氨酸脱羧酶（ODC）活性将是维生素B - 6营养状况的敏感功能指标。正如预期的那样，在较高维生素B - 6水平下，小麦麸质饲料使体重增加降低了约17%。然而，通过静态指标（血浆和组织中B - 6维生素形式的浓度）和功能指标（色氨酸负荷试验）证明，与酪蛋白喂养组相比，麸质喂养组的维生素B - 6营养状况并不更差。在维生素B - 6摄入量较高的三个水平下，肝脏、肾脏和小肠中ODC（全酶和总酶）的活性没有显著变化。在酪蛋白喂养组中，与较高B - 6水平相比，饲料中含0.0毫克维生素B - 6/千克的大鼠这些组织中的总ODC活性高出两到五倍，而肝脏和肾脏中ODC mRNA丰度没有相应差异。血浆、肝脏、肾脏和肠道中B - 6维生素形式的浓度（血浆中磷酸吡哆醛除外）随饲料中维生素B - 6呈线性增加。这些数据表明，以小麦麸质形式提供的低质量蛋白质会抑制生长，但不会影响维生素B - 6营养状况，并且ODC活性不是边缘性维生素B - 6状况的敏感功能指标。
