Objective To determine the effects of zine-deficiency and zine-excess on hone metabolism. Methods We developed the culture model of fetal mouse limbs (16th day) cultivated in self-made rotator with continuing flow of ...Objective To determine the effects of zine-deficiency and zine-excess on hone metabolism. Methods We developed the culture model of fetal mouse limbs (16th day) cultivated in self-made rotator with continuing flow of mixed gas for six days in vitro. The cultured limbs were examined by the techniques of 45Ca tracer and X-roentgenography. Results The right limbs cultivated had longer bone length, higher bone density than the left limbs uncultivated from the same embryo; and histologically, the right limbs had active bone cell differentiation, proliferation, increased bone trabecula. clearly calcified cartilage matrix, and osteogenic tissue. Compared with the control group, the zinc-deficient group and zine-excess (Zn2+ l20) μmol/L) group contained less osteocalcin (BGP) and 45Ca content, and lower AKP activity; whereas zine-normal (Zn2+ 45 μmol/L and Zn2+ 70 μmol/L) groups contained more BGP and 45Ca contents, and higher AKP (alkaline phosphatase) activity. Conclusion Both zine-deficiency and zine-excess can alter bone growth and normal metabolism. The results indicate that the culture model of fetal mouse limbs (16th day) in vitro can be used as a research model of bone growth and development.展开更多
The effects of dietary zinc on the immune organs and cellular immunity were investigated in the rats of zinc-deficient(ZD), zinc-excessive(ZE), paired feeding(PF) and ad libitus(AL) groups. The findings were as follow...The effects of dietary zinc on the immune organs and cellular immunity were investigated in the rats of zinc-deficient(ZD), zinc-excessive(ZE), paired feeding(PF) and ad libitus(AL) groups. The findings were as follows: (1) The weight of the thymus and spleen and the ratio with the body weight, the size of the cells,the production of thymic peptides and thymin activity were significantly lower in ZD and ZE groups than in PF and AL groups. (2) The total number of the cells in G_0/G_1 phase of T-and B-cells and bone marrow cells were significantly higher in ZD and ZF groups than in PF and AL groups while that of the cells in S and G_2/M phases were significantly lower in ZD and ZE groups than in PF and AL groups. (3) The cellular DNA, RNA and protein content in the thymus, spleen and bone marrow were significantly lower in ZD and ZE groups than in PF and AL groups.(4) The ￣3H-TdR incorporation rate of splenic T-and B-cells , IL-2 activity, plasma level of TNF and nitrogen oxide(NO) were significantly lower in ZD group than in PF group. (5) The leucocyte count of the perpheral blood,the percentage of lymphocytes, the bacteriocidal activity of phagocytes, and the phagocytic rate and index of abdominal phagocytes were significantly lower in ZD and ZE groups than in PF and AL groups. These findings indicate that an adequate amount of dietary zinc is essential for the development of immune organs and the promotion of cellular immunity while deficiency or excess of zinc is able to damage the immune function.展开更多
基金This work was supported by Grant 39600122 from the National Natural Science Foundation of China.
文摘Objective To determine the effects of zine-deficiency and zine-excess on hone metabolism. Methods We developed the culture model of fetal mouse limbs (16th day) cultivated in self-made rotator with continuing flow of mixed gas for six days in vitro. The cultured limbs were examined by the techniques of 45Ca tracer and X-roentgenography. Results The right limbs cultivated had longer bone length, higher bone density than the left limbs uncultivated from the same embryo; and histologically, the right limbs had active bone cell differentiation, proliferation, increased bone trabecula. clearly calcified cartilage matrix, and osteogenic tissue. Compared with the control group, the zinc-deficient group and zine-excess (Zn2+ l20) μmol/L) group contained less osteocalcin (BGP) and 45Ca content, and lower AKP activity; whereas zine-normal (Zn2+ 45 μmol/L and Zn2+ 70 μmol/L) groups contained more BGP and 45Ca contents, and higher AKP (alkaline phosphatase) activity. Conclusion Both zine-deficiency and zine-excess can alter bone growth and normal metabolism. The results indicate that the culture model of fetal mouse limbs (16th day) in vitro can be used as a research model of bone growth and development.
文摘The effects of dietary zinc on the immune organs and cellular immunity were investigated in the rats of zinc-deficient(ZD), zinc-excessive(ZE), paired feeding(PF) and ad libitus(AL) groups. The findings were as follows: (1) The weight of the thymus and spleen and the ratio with the body weight, the size of the cells,the production of thymic peptides and thymin activity were significantly lower in ZD and ZE groups than in PF and AL groups. (2) The total number of the cells in G_0/G_1 phase of T-and B-cells and bone marrow cells were significantly higher in ZD and ZF groups than in PF and AL groups while that of the cells in S and G_2/M phases were significantly lower in ZD and ZE groups than in PF and AL groups. (3) The cellular DNA, RNA and protein content in the thymus, spleen and bone marrow were significantly lower in ZD and ZE groups than in PF and AL groups.(4) The ￣3H-TdR incorporation rate of splenic T-and B-cells , IL-2 activity, plasma level of TNF and nitrogen oxide(NO) were significantly lower in ZD group than in PF group. (5) The leucocyte count of the perpheral blood,the percentage of lymphocytes, the bacteriocidal activity of phagocytes, and the phagocytic rate and index of abdominal phagocytes were significantly lower in ZD and ZE groups than in PF and AL groups. These findings indicate that an adequate amount of dietary zinc is essential for the development of immune organs and the promotion of cellular immunity while deficiency or excess of zinc is able to damage the immune function.
