Davis C D, Schafer D M, Finley J W
United States Department of Agriculture, Agriculture Research Service, Grand Forks Human Nutrition Research Center, North Dakota 58202-9034, USA.
Biol Trace Elem Res. 1998 Summer;64(1-3):61-74. doi: 10.1007/BF02783325.
Neurologic and radiologic disorders have been reported to occur in miners inhaling manganese (Mn)-laden dust and in humans receiving long-term parenteral nutrition. These abnormalities have been attributed to Mn intoxication because of elevated serum Mn concentrations. Because the liver, by way of the bile, is the major route of Mn excretion, it is possible that anything that decreases biliary excretion could increase accumulation of Mn in the brain. The purpose of this study was to determine whether biliary ligation would increase Mn accumulation in the brain of rats that were exposed to deficient or adequate amounts of dietary manganese. The first experiment had a 2 x 3 factorial design, two levels of Mn (0 or 45 microg/g diet) and three surgical treatments (control, sham, or bile-ligation). Animals were sacrificed 10 d after being fed 54Mn. In experiment 2, animals that had a sham operation or bile-ligation were sacrificed at 8 time points after being injected intraportally with 54Mn complexed to albumin. The biliary-ligated animals had a significantly (p < 0.001) smaller percentage of the 54Mn in their brains (when expressed as a percentage of whole animal 54Mn) than the sham-operated animals. Mn deficiency had a similar effect. However, we did observe an increased accumulation of the radioisotope in the brain over time. Therefore, in short-term studies, biliary-ligated rats do not appear to be a good model for Mn accumulation in the brains of people with cholestatic liver disease.
据报道，吸入含锰（Mn）粉尘的矿工以及接受长期肠外营养的人群会出现神经和放射学疾病。这些异常现象被归因于血清锰浓度升高导致的锰中毒。由于肝脏通过胆汁是锰排泄的主要途径，因此任何降低胆汁排泄的因素都可能增加锰在大脑中的蓄积。本研究的目的是确定胆管结扎是否会增加暴露于缺乏或适量膳食锰的大鼠大脑中的锰蓄积。第一个实验采用2×3析因设计，锰有两个水平（0或45微克/克饮食），手术治疗有三种（对照、假手术或胆管结扎）。给动物喂食54Mn后10天处死。在实验2中，对接受假手术或胆管结扎的动物经门静脉注射与白蛋白结合的54Mn后，在8个时间点处死。与假手术动物相比，胆管结扎动物大脑中54Mn的百分比（以全动物54Mn的百分比表示）显著降低（p<0.001）。锰缺乏也有类似的效果。然而，我们确实观察到随着时间的推移，大脑中放射性同位素的蓄积增加。因此，在短期研究中，胆管结扎的大鼠似乎不是胆汁淤积性肝病患者大脑中锰蓄积的良好模型。
