缺镁大鼠的草酸盐代谢

Oxalate metabolism in magnesium-deficient rats.

作者信息

Rattan V, Thind S K, Jethi R K, Sidhu H, Nath R

机构信息

Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India.

出版信息

Magnes Res. 1993 Jun;6(2):127-33.

PMID:8274358

Abstract

Male weanling rats were maintained on magnesium-deficient diet for 30 d and compared with pair-fed control rats fed magnesium-supplemented diet. Magnesium deficiency led to slow growth and finally to a significant decrease in body weight (P < 0.001) accompanied by a significant hypomagnesaemia, hypomagnesuria and hyperoxaluria (P < 0.001 in each case) in experimental rats as compared to the control rats. Magnesium deficiency altered the glyoxylate metabolism in the liver and kidney mitochondria by significantly decreasing glyoxylate oxidation (by 26 per cent in liver and 17 per cent in kidney) and activity of alpha-ketoglutarate:glyoxylate carboligase enzyme (by 35 per cent in liver and 27 per cent in kidney) in the experimental animals. A significant increase in the specific activities of glycolic acid oxidase (P < 0.001) and glycolic acid dehydrogenase (P < 0.01) and a significant decrease in alanine transaminase (P < 0.01) was also observed in magnesium-deficient rats. No change in liver and kidney lactate dehydrogenase was observed. Thus magnesium deficiency in rats leads to accumulation of glyoxylate in the tissues, a part of which is converted into oxalate, thereby promoting hyperoxaluria.

摘要

将雄性断乳大鼠用缺镁饮食饲养30天，并与喂食补充镁饮食的配对对照大鼠进行比较。与对照大鼠相比，缺镁导致实验大鼠生长缓慢，最终体重显著下降（P < 0.001），同时伴有明显的低镁血症、低镁尿症和高草酸尿症（每种情况P < 0.001）。缺镁通过显著降低乙醛酸氧化（肝脏中降低26%，肾脏中降低17%）以及实验动物肝脏和肾脏中α-酮戊二酸：乙醛酸羧化酶的活性（肝脏中降低35%，肾脏中降低27%），改变了肝脏和肾脏线粒体中的乙醛酸代谢。在缺镁大鼠中还观察到乙醇酸氧化酶（P < 0.001）和乙醇酸脱氢酶（P < 0.01）的比活性显著增加，以及丙氨酸转氨酶（P < 0.01）显著降低。未观察到肝脏和肾脏乳酸脱氢酶的变化。因此，大鼠缺镁会导致组织中乙醛酸积累，其中一部分会转化为草酸盐，从而促进高草酸尿症。