Walther F, Heine W, Richter I, Wutzke K D
Klinik für Kinderheilkunde, Wilhelm-Pieck-Universität, Rostock, DDR.
Biomed Biochim Acta. 1987;46(11):803-8.
Absorption of D-[alpha-15N]lysine and L-[alpha-15N]lysine following an oral single pulse labelling at a dosage of 5 mg 15N'/kg body weight was compared in four subjects aged 4 to 14 months. The wastages of 15N' in the faeces ranged from 0.3 to 5% of the input implying comparably high absorption rates of both the lysine enantiomers. Only about 7.6% of the 15N from the alpha-amino groups were found in the urine after loading with L-[alpha-15N]lysine. In contrast, about 80.2% of the 15N' dose from D-[alpha-15N]lysine were eliminated renally. However, 18.5% of the 15N' dose on an average were retained after D-[alpha-15N]lysine administration. This is certainly due to a partial desamination of D-lysine. The faecal bacteria isolated from the faeces contained no or only small amounts of 15N' after D-[alpha-15N]lysine loading. Following L-[alpha-15N]lysine administration a measurable 15N enrichment of the faecal bacteria of up to 0.09 at % excess was achieved in almost all cases.
在4名4至14个月大的受试者中，比较了口服单脉冲标记剂量为5mg 15N'/kg体重的D-[α-15N]赖氨酸和L-[α-15N]赖氨酸后的吸收情况。粪便中15N'的排泄量占摄入量的0.3%至5%，这意味着两种赖氨酸对映体的吸收率相当高。用L-[α-15N]赖氨酸负荷后，尿液中仅发现约7.6%的α-氨基15N。相比之下，D-[α-15N]赖氨酸剂量中约80.2%的15N'经肾脏排泄。然而，给予D-[α-15N]赖氨酸后，平均有18.5%的15N'剂量被保留。这肯定是由于D-赖氨酸的部分脱氨基作用。在D-[α-15N]赖氨酸负荷后，从粪便中分离出的粪便细菌不含15N'或仅含少量15N'。给予L-[α-15N]赖氨酸后，几乎在所有情况下，粪便细菌的15N富集量都达到了可测量的高达0.09原子百分比过剩。
