大鼠烫伤后补锌对血清和组织锌、钙离子的影响

Effects of zinc supplementation on zinc and calcium levels in serum and tissue in burned rats

目的 探讨大鼠烫伤后补锌对血清和组织锌离子、钙离子的影响及其意义。方法 SD大鼠80只随机分为对照组和烫伤后正常进食组、创面补锌组、口饲补锌组，伤后1、3、7天活杀大鼠，留取标本检测血清、肝脏、骨骼及烫伤皮肤等组织中Zn^2＋、Ca^2＋含量。结果 烫伤后正常进食组、创面补锌组血清Zn^2＋明显下降，约低于伤前1／3，而口饲补锌组明显上升，高达13．1～16．2μmol／L。肝Zn^2＋各组均呈上升趋势，以口饲补锌组最明显，补锌第1天升至41．6μg／g。肝脏Ca^2＋正常进食组、创面补锌组增加，烫伤第1天正常进食组升至30．8mg／g，口饲补锌组低于伤前和正常进食组、创面补锌组。骨Zn^2＋、骨Ca^2＋在烫伤后各组均呈递减趋势，以正常进食组最明显，烫伤后第7天，骨Zn^2＋和Ca^2＋分别降至41．5μg／g和50．2μg／g。烫伤皮肤Zn^2＋在伤后第1天正常进食组、创面补锌组下降，口饲补锌组却明显升高至27．1μg／g，第3、7天，各组均逐渐上升，以创面补锌组最明显，达34．3μg/g。烫伤皮肤Ca^2＋各组均呈大幅度递增，其中以正常进食组最明显，烫伤后第7天升至5．4mg／g，高出对照组67．5倍，创面补锌组明显低于正常进食组。结论 烫伤后及补锌血清、组织中的Zn^2＋、Ca^2＋含量均出现明显的变化，不同途径补锌对组织中Ca^2＋含量也有影响，其机制需进一步探讨。

Objective To explore the effects of zinc supplementation on zinc and calcium levels in serum and tissue in burned rats. Methods Eighty SD rats were randomly divided into C group （ control group without scald, n =8）, and N, W, H groups （each consisting of 24 rats）, in which the rats were exposed to scalding resulting in partial thickness burns covering 15% of the total body surface area on the back, and then they were fed with diets containing zinc 40μg/g in N and W groups, and 80 μg/g in H group. A cream containing zinc 761.1μg/g was applied on the wound in W group at the same time. Eight rats of each group were sacrificed on day 1, 3 and 7 after scald respectively. Venous blood and samples of liver, femur and scald skin were harvested. Zinc and calcium contents in serum and tissues were determined with atomic absorption spectrophotometer. Results The serum Zn^2 ＋ levels in N,W groups were lower than C group, however, it was obviously higher in H group （up to 16. 2μmol/L ） on day 1 after scald. The liver Zn^2＋ showed an increasing tendency in all groups, while Ca^2＋ level declined in H group, but increased in N,W group. The bone Zn^2 ＋ and Ca^2 ＋ levels showed a progressive declination in all groups from day 1 to 7 after scald. The changes were more obviously in N group than H group （ P 〈 0. 05 ）. The Zn^2 ＋ content of the scalded skin increased obviously in H group on first day after scald and in W group on 7th day after scald. The Ca^2＋ contents of scalded skin showed marked increases in all groups, especially in N group, but least in W group. Condusion There are obvious changes in Zn^2＋ and Ca^2＋ contents of serum and tissues after scald injury and zinc supplementation. The effects of zinc supplementation on calcium level in the tissue need to be further studied.