左旋咪唑对牛乳脂肪球膜碱性磷酸酶和5'-核苷酸酶的抑制作用。

Levamisole inhibition of alkaline phosphatase and 5'-nucleotidase of bovine milk fat globule membranes.

Khodaparast-Sharifi S H, Snow L D

Department of Chemistry, Louisiana Tech University, Ruston 71272.

Int J Biochem. 1989;21(4):401-5. doi: 10.1016/0020-711x(89)90364-9.

Abstract

The effect of levamisole (LMS) on alkaline phosphatase (EC 3.1.3.1) and 5'-nucleotidase (EC 3.1.3.5) activities of bovine milk fat globule membranes (MFGM) was examined. 2. LMS inhibited MFGM alkaline phosphatase activity in a concentration-dependent manner with 50% inhibition produced by 49 +/- 23 microM LMS. 3. 5'-Nucleotidase was resistant to LMS inhibition with 30.9% inhibition produced by 10 mM LMS, the highest concentration tested. 4. LMS was an uncompetitive inhibitor of MFGM alkaline phosphatase with a Ki of 45 +/- 6 microM. 5. The extent of LMS inhibition of alkaline phosphatase was dependent on the substrate utilized in the assay. 6. The effect of LMS on bovine MFGM alkaline phosphatase was similar to LMS effects on other mammalian alkaline phosphatases of liver/kidney/bone/placental isoenzyme origin.

摘要

研究了左旋咪唑（LMS）对牛乳脂肪球膜（MFGM）碱性磷酸酶（EC 3.1.3.1）和5'-核苷酸酶（EC 3.1.3.5）活性的影响。2. LMS以浓度依赖的方式抑制MFGM碱性磷酸酶活性，49±23微摩尔/升的LMS产生50%的抑制作用。3. 5'-核苷酸酶对LMS抑制具有抗性，10毫摩尔/升（测试的最高浓度）的LMS产生30.9%的抑制作用。4. LMS是MFGM碱性磷酸酶的非竞争性抑制剂，其抑制常数（Ki）为45±6微摩尔/升。5. LMS对碱性磷酸酶的抑制程度取决于测定中使用的底物。6. LMS对牛MFGM碱性磷酸酶的作用类似于LMS对其他源自肝脏/肾脏/骨骼/胎盘同工酶的哺乳动物碱性磷酸酶的作用。