香豆素对实验性大鼠草酸钙结石形成的影响

An experimental study on effects of coumarol diet on calcium oxalate crystalization in rat kidney

应用偏光显微镜和解剖镜观察ＶｉｔａｍｉｎＫ（Ｖｉｔ－Ｋ）拮抗剂香豆素对大鼠草酸钙结石形成影响，观察到香豆素显著地增加大鼠肾内草酸钙结晶数目，肾组织匀浆中草酸含量（１．１４±０．７３ｍｇ／ｇ）也显著高于对照组（０．０３６±０．１５ｍｇ／ｇ，Ｐ＜０．０５）。当停用香豆素后，肾内草酸钙结晶数又可减少。推测香豆素可拮抗Ｖｉｔ－Ｋ使得肾内依赖Ｖｉｔ－Ｋ的羧化作用减弱，肾内草酸钙抑制物Ｎｅｐｈｒｏｃａｌｃｉｎ（Ｎｃ）中谷氨酸转化成γ－羧基谷氨酸（Ｇｌａ）减少，Ｎｃ与钙结合减少，对草酸钙结晶抑制活性降低，易发生草酸钙结石。提示Ｖｉｔ－Ｋ缺乏可促进肾结石形成。

Coumarol diet a vitamin K-antagonist,may significantly increase the counts of calcium oxalate in the rat kidneys observed with polarizing and stereoscopic microscopy.The oxalate concentration in renal homogenixation is significantly higher in the group on coumarol diet than that of controls.When the vitamin K-antagonist was cut off from diet, the counts of calcium oxalate crystal was found to be reduced. We suggest that coumarol might antagonize the effect of vitamin K on carboxylation. The exchange of glutamic acid to rcarboxyglutamic acid in nephrocalcin(Nc)falls, Which reduces the combinatin of Nc with calcium and so reduces the action of Nc to calium oxalate crystal inh ibitor. As a result calcium oxalatal cystal in the rat kidney increases.We conclude that itamin k-deficiency increases for mation of renal stone.