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

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 40 microg/g in N and W groups, and 80 microg/g in H group. A cream containing zinc 761.1 microg/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 16.2 micromol/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.

Conclusion: 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.