4种血清酶在三硝基甲苯染毒致大鼠肝损伤中的变化及意义

目的]观察三硝基甲苯(TNT)染毒致大鼠肝损伤时血清乳酸脱氢酶(LDH)、谷氨酸氨基移换酶(ALT)、天门冬酸氨基移换酶(AST)和碱性磷酸酶(ALP)的活力变化情况,并探讨其意义。方法]以50、100和200mg/kg体重剂量的TNT对大鼠每天一次经口染毒,分别于染毒2、4、6和8周后处死,测定血和肝组织TNT代谢产物2,6-二硝基-4-氨基甲苯(DNAT)水平、血靛青绿(ICG)10min滞留率(ICG_(R10))和血清LDH、ALT、AST、ALP的变化情况。结果]TNT染毒大鼠血和肝组织DNAT均比对照组有明显升高,TNT染毒剂量与大鼠血清或肝组织DNAT呈显著性相关(P<0.01),血清与肝组织DNAT呈显著性相关(P<0.01);各TNT染毒组大鼠血清ICG_(R10)明显高于对照组。TNT高剂量染毒组大鼠血清LDH、ALT、AST和ALP活力有所降低,其他剂量组与对照组相比未见显著性变化;血清或肝组织DNAT与血清LDH呈显著性负相关(P<0.05或0.01),与ALT、AST和ALP均负相关,但未见显著性(P>0.05)。结论]血清LDH、ALT、AST和ALP指标对TNT染毒诱导的大鼠肝损伤的反应并不敏感,似与TNT代谢产物DNAT对血清4种酶活力可能具有的一定抑制作用有关。

A Study of Serum LDH, ALT, AST and ALP Activity Change in Rats Exposed to TNT

Objective]To examine the changes of serum LDH,ALT,AST,ALP activities in rats exposed to TNT and its significance.Methods]Rats were exposed to a dose of 50,100 and 200 mg/kg-body weight TNT peroral daily for 2,4,6 and 8 weeks.The metabolite of TNT-DNAT level in liver tissue and blood,ICG retention rate test of blood and the serum LDH,ALT, AST,ALP activities were measured.Results]The DNAT increased significantly both in blood and liver tissue with a manner dependent on exposure time and dose of TNT.The DNAT in liver tissue and in blood correlated with each other significantly(P<0.01).The blood ICG retention rates in all TNT exposure group rats were obviously increased compared with that of control group. In higher TNT dose exposure group rats,the levels of serum LDH,ALT,AST and ALP activities were obviously lower than those of control group,but there were not any greater difference on the serum ALT,ALP and ALP activity between lower dose of TNT exposure group and control group rats.The level of DNAT in liver tissue or blood were obviously negative correlated with the serum LDH activity(P<0.05 or 0.01),but not significantly negative correlated with serum ALT,AST,ALP activities.Conclusion] The results demonstrated that the DNAT may have some inhibit effect on the activity of serum enzyme,serum LDH,ALT,ASP and ALP might be not the sensitive indices for the evolution on liver injury caused by TNT exposure in rats.