Foster D M, Aamodt R L, Henkin R I, Berman M
Am J Physiol. 1979 Nov;237(5):R340-9. doi: 10.1152/ajpregu.1979.237.5.R340.
A quantitative model is developed that describes the kinetics of the early phases of zinc metabolism in humans. The model is based on averaged data obtained over 5 days from 17 atients with smell and/or taste dysfunction who were given 69mZn in trace amounts orally and intravenously. A function describing the rate of entry of 69mZn into systemic plasma following ingestion of the isotope is derived showing that about 37% of the ingested zinc enters plasma. Gastrointestinal absorption is essentially completed by 4 h. Sixty-seven percent of the absorbed zinc in the portal circulation is extracted by the liver before being released into the systemic circulation and agrees with the calculated extraction efficiency from the systemic circulation. There are both rapid and slow exchnage phases between plasma and liver and between plasma and red cells. The calculated steady-state zinc values for plasma, red cells, and liver agree with previously reported measured values implying there are no additional zinc pools in these tissues. The tracer data, however, account for only 10% of total body zinc, the remaining 90% in tissues whose kinetics are too slow to be resolved from a 5-day study.
建立了一个定量模型，该模型描述了人体锌代谢早期阶段的动力学。该模型基于从17名嗅觉和/或味觉功能障碍患者中获取的平均数据，这些患者经口服和静脉注射微量的69mZn，并持续观察5天。推导出一个描述摄入该同位素后69mZn进入全身血浆速率的函数，结果表明约37%的摄入锌进入血浆。胃肠道吸收在4小时内基本完成。门静脉循环中67%被吸收的锌在释放到体循环之前被肝脏摄取，这与从体循环计算得出的摄取效率相符。血浆与肝脏之间以及血浆与红细胞之间存在快速和缓慢的交换阶段。计算得出的血浆、红细胞和肝脏的稳态锌值与先前报道的测量值一致，这意味着这些组织中不存在额外的锌池。然而，示踪数据仅占全身锌的10%，其余90%存在于动力学过慢以至于无法从为期5天的研究中解析出来的组织中。
