大鼠烫伤后补锌对血清、组织中锌、钙离子的影响

The effect of zinc supplementation on serum and tissue calcium levels in scalded rats

目的:观察大鼠烫伤及补锌对血清、组织中锌(Zn^(2+))、钙(Ca^(2+))离子的影响。方法:背部15%深Ⅱ°烫伤大鼠随机分为N组(正常进食组,饲料含Zn^(2+) 40 μg/g)、W组(创面补锌组,饲料含Zn^(2+)40 μg/g,同时创面涂银锌霜,含Zn^(2+)761.1 μg/g)、H组(口饲补锌组,饲料含Zn^(2+)80 μg/g);分别于伤后1、3、7天活杀大鼠,留取标本检测。结果:烫伤后第1天N组、W组血清Zn^(2+)明显降低,而后回升,伤后7天接近伤前水平;而H组伤后明显升高。N组、W组血清Ca^(2+)伤后降低,H组上升。伤后第1、3天各组肝脏Zn^(2+)均呈上升趋势,以H组最明显(P<0.01)。N、W组肝脏Ca^(2+)均升高,H组低于伤前和N、W组(P<0.01)。烫伤后各组骨Zn^(2+)均呈递减趋势,以N组降低幅度最大,明显低于H组(P<0.01)。伤后N、W组骨Ca^(2+)逐渐下降,N组第7天明显低于H组(P<0.05)。伤后第1天,N、W组烫伤皮肤Zn^(2+)下降,H组明显升高,第3、7天,各组皮肤Zn^(2+)均逐渐上升,以W组最明显。各组烫伤皮肤中Ca^(2+)均呈大幅度递增(P<0.01),其中以N组最明显;W组明显低于N组(P<0.01)。结论:烫伤后血清、骨骼Ca^(2+)含量降低;肝脏、烫伤皮肤Ca^(2+)含量增加,可能与Ca^(2+)体内异常分布、细胞内钙超载有关;口饲补Zn^(2+)主要提高血清、肝脏Zn^(2+),降低肝组织Ca^(2+)含量,创面补Zn^(2+)主要增加烫伤皮肤Zn^(2+),降低烫伤皮肤Ca^(2+)含量,Zn^(2+)可能具有减轻细胞内钙超载的作用。

Objective: To study the effect of zinc supplementation on zinc and calcium ion levels in serum and tissue in scalded rats. Methods: 80 SD rats were randomly divided into control group and N, W, H groups. Animals in N, W, H groups were subjected to a 15% TBSA full-thickness scald injury, and then were fed on dietscontaining zinc 40 ug/g in N, W groups and 80 ug/g in H group. An ointment containing zinc 761.1 ug/g was applied on scalded skin in W group at the same time. Zinc and calcium ions concentrations in serum, liver, bone, scalded skin were measured on days 1, 3, 7 after scald, respectively. Results: Serum Zn^(2+) levels in N and W groups were lower than that in controls (0.66 μg/ml), but it obviously an increased in H group (up to 1.06μg/ml on day 1 after scald). Liver Zn^(2+) showed an increasing tendency in all groups, reaching 41.7 μg/g on day 1 after scald in H group, and being 1.75-fold as much as N group (P<0.01). Contents of calcium in liver increased in N and W groups and declined in H group comparing with controls. Zn^(2+) levels in bone showed a decreasing tendency in all groups from day 1 to 7 after scald, and it was from 68. 9μg/g to 41.5 μg/g in N group,which was markedly lower as compared with H group (P<0.01). Ca^(2+) level in bone was 73.3mg/g prior to scald, it was 50.2 mg/g in N group on day 7, being 15.7 mg/g less than H group (P<0.05). Zn^(2+) content of scalded skin declined in N and W groups, however, Zn^(2+) content obviously increased in H group on first day after scald, reaching a peak value (34.4 μg/g) in W group on day 7. Ca^(2+) contents of scald skin increased markedly increase in all group, especially in N group, being 3.0, 22.5, 66.2-fold higher than baseline value on days1, 3, 7, respectively (P<0.01). Its amount in W group was less than that in N group. Conclusion: The contents of Ca^(2+) were decreased in serum, bone, and increased in liver and scalded skin, which might be related to abnormal distribution of Ca^(2+) in the body and calcium overload in cells. Supplementation of zinc by diet could lead to increase in Zn^(2+) levels in serum and liver and decrease in Ca^(2+) contents. Supplementation of zinc through wound could increase Zn^(2+) content and reduce the Ca^(2+) level in skin. Zinc may posses a role in mitigating calcium overload in cells.