The effects of a low level of dietary cadmium on blood pressure, '24Na, '42K, andwater retention in growing rats.

The effects of 5 pg Cd per millilter of drinking water on body weight gain, food intake, systolic blood pressure, '24Na, '42K; and water retention and freference for NaCl solution in male and female rats were studied. After 205 days, Cd had no significant effect on weight gain, food intake, water intake, or feed efficiency. The'24Na retention of the Cd-fed male and female rats was greater at 161 days than in the control animals and was significantly greater (P less than 0.05) in the Cd-treated females than in the control females at 294 days. In vivo retention of '42K was significantly greater in the Cd-treated males than in the control males at 189 days, butthe oppisite was true of the Cd-treated females in comparison with female control animals. There were no significant differences between treatments in '42K retention after 330 days. No significant differences were found between treatments in systolic blood pressure. Water retention was significantly greater in the Cd-treated males and females than in the control animals after 320 days. Preference for 0.20 M NaCl was significantly greater in the Cd-fed males than in the control males at 277 days.Possible mechanisms which might explain the sodium retention in thhe Cd-fed rat are discussed.     

Ethics: responsible scientific conduct

Body composition and measures of obesity were evaluated in 59 subjects with myelomeningocele (MMC), aged 0.3-29 y, by anthropometry and measures of body cell mass (BCM) and intra- and extracellular water (ICW and ECW), derived from total body potassium and deuterium-isotope dilution; these results were compared with reference data. Body composition was normal in preambulatory children with MMC. Beyond ages 3-4 y there was significant depletion of BCM and total body water, with maldistribution of water (increased ECW and decreased ICW) and increased percentage body fat above that expected for age and sex. These findings were more pronounced in females and in those with high lesions, and were less pronounced in those who remained ambulatory. These changes may result in metabolic and nutritional maladaption during stress. The relation of BCM, total body water depletion and increased ECW to decreasing ambulatory activity suggests that early nutritional and mobility programs warrant further study.     

Severe zinc deficiency: effects on the distribution of nine elements (potassium, phosphorus, sodium, magnesium, calcium, iron, zinc, copper and manganese) in regions of the rat brain

The effect of severe zinc deficiency on the distribution of nine elements (potassium, phosphorus, sodium, magnesium, calcium, iron, zinc, copper and manganese) in brain regions (olfactory lobes, right and left hippocampi, cerebellum and the rest of the brain) has been studied. After male rats (30 days old) were fed a zinc-deficient diet for 28 days, the zinc concentration of most brain parts was similar to zinc-adequate control values. Olfactory lobe zinc, on the other hand, was slightly depressed. However, the levels of other metals were dependent on zinc nutriture. Zinc deficiency caused an elevation in copper concentrations in most brain parts. Restriction of food intake caused a similar increase in brain copper but generally the effect was less than with zinc deficiency. Levels of calcium, manganese, sodium and potassium, in certain brain regions, also appeared to be altered by the zinc status of an animal. Of the minerals examined, only zinc and copper displayed asymmetrical distribution between the right and left hippocampus, and severe zinc deficiency did not affect lateral distribution of these trace metals in the hippocampus. The data suggest the hypothesis that changes in brain metal content, associated with zinc deficiency, contribute to the behavioral abnormalities that occur.     

不同补锌方法对儿童免疫功能的影响

研究不同补锌方法（补锌，补充微量营养素，补充锌加微量营养素）改善缺锌儿童免疫功能的作用，结果显示：实验１０ｗｋ后，三个实验组缺锌儿童血清锌浓度明显升高，同时淋巴细胞刺激指数明显高于对照组，流式细胞仪检测细胞周期显示对照组Ｇ０／Ｇ１期细胞增多，而实验组Ｓ＋Ｇ０／Ｇ１期细胞增多，细胞处于增殖活化状态。三组中又以锌＋微量营养素作用效果最好。表明：锌和微量营养素单独使用均增强缺锌儿童的免疫功能，但锌和微量     

Alterations in the postnatal development of the cerebellar cortex due to zinc deficiency. I. Impaired acquisition of granule cells

The effects of zinc deficiency on cerebellar development were investigated in suckling rats. In 21-day-old zinc-deficient rats the cerebellum as well as the whole brain was reduced in size. The cerebellar cortex was underdeveloped and showed a persistence of the external granule cell layer, a reduction in the thickness of molecular layer and a decrease in the area of the internal granule cell layer. Lobular variations were present. Along the posterior superior fissure there was approximately a 60% reduction in the number of granule cells and in the number of granule cells per Purkinje cell. It was suggested that the reduction in the number of granule cells was predominantly the result of impaired cell proliferation in the external granule cell layer. Comparisons with undernourished, pair-fed pups indicated that the effects of zinc deficiency could not be mediated totally through the reduced food consumption experienced by zinc deficient dams.