Decrease in catechol-O-methyltransferase activity in the liver of streptozotocin-induced diabetic rats

被引：14

作者：

Wang, JP

Liu, IM

Tzeng, TF

Cheng, JT ^{[1
]}

机构：

[1] Natl Cheng Kung Univ, Coll Med, Dept Pharmacol, Tainan 70101, Taiwan

[2] Mackay Mem Hosp, Dept Orthoped, Taipei, Taiwan

[3] Kaohsiung Med Univ, Coll Med, Dept Internal Med, Kaohsiung, Taiwan

来源：

CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY | 2002年 / 29卷 / 5-6期

关键词：

catechol-O-methyltransferase; insulin; metanephrine; phlorizin;

D O I：

10.1046/j.1440-1681.2002.03673.x

中图分类号：

R9 [药学];

学科分类号：

1007 ;

摘要：

1. The present study compared the activity of catechol- O -methyltransferase (COMT) in the liver and plasma of streptozotocin (STZ)-induced diabetic rats with that in normal rats. The activity of COMT was estimated by the metabolism of noradrenaline to metanephrine (MN), both measured by high-performance liquid chromatography with electrochemical detection. 2. Formation of MN was decreased in the liver of STZ- diabetic rats compared with normal rats. The amount of MN was also decreased in plasma obtained from STZ-diabetic rats. A Michaelis-Menten plot showed a reduction in the maximum velocity and an increase in the K-m for COMT in liver samples from STZ-diabetic rats. 3. The role of hyperglycaemia in the lowering of COMT activity was then investigated using phlorizin or insulin at doses sufficient to normalize plasma glucose from STZ-diabetic rats. Both insulin and phlorizin treatment of STZ-diabetic rats for 4 days restored the activity of COMT to that seen in normal rats. Thus, correction of hyperglycaemia in STZ-diabetic rats can reverse the decrease in COMT activity. The activity of COMT is lower in STZ-diabetic rats than in normal rats mainly due to the higher plasma glucose.

引用

页码：419 / 422

页数：4

共 15 条

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