Root E J, Combs G F
Department of Home Economics, University of Texas, Austin 72712.
Proc Soc Exp Biol Med. 1988 Apr;187(4):513-21. doi: 10.3181/00379727-187-42697.
Severe uncomplicated selenium (Se) deficiency was produced in chicks by feeding, from 1 day of age, a purified diet that contained 0.010 ppm Se but was adequate with respect to all other known nutrients. The deficiency was characterized by depressions in rate of growth and efficiency of feed utilization and by reductions in the plasma activity of Se-dependent glutathione peroxidase (SeGSHpx) by 85-97% from levels in chicks fed the basal diet supplemented with 0.20 ppm Se as Na2SeO3. Histological observations of the target organ of Se deficiency in the chick, i.e., the pancreas, using transmission electron microscopy, showed severe losses of endoplasmic reticulum (ER) and absence of secretory granules in acinar cells of Se-deficient animals. These effects were not uniform within individuals, as Se-deficient pancreases also showed areas of unaffected acini. By 14 days of age, Se-deficient pancreases contained many apparently undifferentiated cells, which were absent from pancreases of Se-fed chicks. It is noteworthy that abnormal mitochondria were not observed in any pancreas sections. It is concluded that the metabolic consequences of severe uncomplicated Se deficiency in the chick result from the disruption of ER and loss of functional acinar cells, rather than to damage to mitochondria as previously suggested.
从1日龄起，给雏鸡喂食一种纯化日粮，该日粮含0.010 ppm硒，但其他所有已知营养素含量充足，由此导致雏鸡出现严重的单纯性硒缺乏。这种缺乏的特征是生长速率和饲料利用效率降低，以及血浆中硒依赖性谷胱甘肽过氧化物酶（SeGSHpx）的活性比喂食添加0.20 ppm硒（以亚硒酸钠形式）的基础日粮的雏鸡降低了85%至97%。使用透射电子显微镜对雏鸡硒缺乏的靶器官即胰腺进行组织学观察，结果显示，缺硒动物的腺泡细胞内质网严重损失，且没有分泌颗粒。这些影响在个体内并不一致，因为缺硒胰腺也有未受影响的腺泡区域。到14日龄时，缺硒胰腺含有许多明显未分化的细胞，而喂食硒的雏鸡胰腺中没有这些细胞。值得注意的是，在任何胰腺切片中均未观察到异常线粒体。得出的结论是，雏鸡严重单纯性硒缺乏的代谢后果是内质网破坏和功能性腺泡细胞丧失所致，而不是如先前推测的那样由线粒体损伤导致。
