Reis B L, Keen C L, Lönnerdal B, Hurley L S
Department of Nutrition, University of California, Davis 95616.
J Nutr. 1988 Mar;118(3):349-61. doi: 10.1093/jn/118.3.349.
Zinc metabolism of adult female C57BL/6J mice varying in age and reproductive status was studied using 65Zn. Animals were injected intraperitoneally with isotope, and whole-body and tissue turnover of 65Zn was measured. Biological half-life of whole-body 65Zn for pregnant females was 129% of that for nonpregnant, nonlactating females of similar age (25.7 and 20.0 d, respectively). Conversely, the half-life of zinc was less for lactating (11.1 d) and aged (15.3 d) females than for either pregnant or nonpregnant, nonlactating young adult females. Retention of 65Zn was generally lower for all tissues of pregnant and lactating dams than for nonpregnant, nonlactating females except for brain and tibia. In aged females, specific activity at 20 d postinjection did not differ from that of nonpregnant, nonlactating young adult females for any tissue except bone. While specific activity of tibia increased during pregnancy and lactation, it was lower in aged females than in nonpregnant, nonlactating young adult females. Increased organ content of zinc resulted from changes in zinc concentration or in organ mass or both, and was supported by increased food intake. Thus, greater food intake for these groups than for young adult females contributed to the higher turnover of tissue 65Zn. Differences in concentrations of Cu, Ca and Mg were also observed among groups for some tissues; the significance of these differences and their relationship to zinc metabolism are not clear.
利用65锌对不同年龄和生殖状态的成年雌性C57BL/6J小鼠的锌代谢进行了研究。给动物腹腔注射该同位素，然后测量全身和组织中65锌的周转率。怀孕雌性小鼠全身65锌的生物半衰期是年龄相近的未怀孕、未哺乳雌性小鼠的129%（分别为25.7天和20.0天）。相反，哺乳期（11.1天）和老龄（15.3天）雌性小鼠的锌半衰期比怀孕或未怀孕、未哺乳的年轻成年雌性小鼠短。除脑和胫骨外，怀孕和哺乳母鼠所有组织中65锌的保留率通常低于未怀孕、未哺乳的雌性小鼠。在老龄雌性小鼠中，注射后20天时，除骨骼外，任何组织的比活度与未怀孕、未哺乳的年轻成年雌性小鼠无差异。虽然胫骨的比活度在怀孕和哺乳期增加，但老龄雌性小鼠的比活度低于未怀孕、未哺乳的年轻成年雌性小鼠。锌器官含量的增加是由锌浓度或器官质量或两者的变化引起的，并得到食物摄入量增加的支持。因此，这些组比年轻成年雌性小鼠摄入更多的食物，这导致组织中65锌的周转率更高。在某些组织的不同组之间也观察到铜、钙和镁浓度的差异；这些差异的意义及其与锌代谢的关系尚不清楚。
