Sertkaya N N, Gorrod J W
Chelsea Department of Pharmacy, King's College, University of London, U.K.
Anticancer Res. 1988 Nov-Dec;8(6):1345-50.
The hydrolysis of three isomeric arylamides 2-acetamidobiphenyl (2-AABP), 3-acetamidobiphenyl (3-AABP) and 4-acetamidobiphenyl (4-AABP) by microsomal carboxylesterases from mouse, hamster, guinea-pig, rat and rabbit livers was investigated. 2-AABP was hydrolysed at the fastest rate in all species except the mouse, the rate of hydrolysis of the 3 and 4 isomers was similar. The hydrolysis of the isomers in all species was inhibited by 10(-4) M paraoxon permitting the general identification of enzyme(s) responsible as "B" esterases. The more selective inhibitors bis-(4-nitrophenyl) phosphate (BNPP) and bis-(4-cyanophenyl) phosphate (BCPP) permitted further characterisation of the esterase(s) as a ES-3 carboxylesterase. However, the hydrolysis of 2-AABP was considerably less sensitive to these inhibitors than 3-AABP and 4-AABP, indicating that 2-AABP is a favoured substrate for the enzyme. The mouse arylamide hydrolysing activity was uniformly less sensitive to both BNPP and BCPP suggesting an enzyme distinct from ES-3 carboxylesterase may be involved.
研究了来自小鼠、仓鼠、豚鼠、大鼠和兔肝脏的微粒体羧酸酯酶对三种异构芳基酰胺2-乙酰氨基联苯（2-AABP）、3-乙酰氨基联苯（3-AABP）和4-乙酰氨基联苯（4-AABP）的水解作用。除小鼠外，2-AABP在所有物种中的水解速度最快，3和4异构体的水解速度相似。所有物种中异构体的水解均受到10^(-4) M对氧磷的抑制，从而可以将负责的酶大致鉴定为“B”酯酶。更具选择性的抑制剂双（4-硝基苯基）磷酸酯（BNPP）和双（4-氰基苯基）磷酸酯（BCPP）可进一步将酯酶表征为ES-3羧酸酯酶。然而，2-AABP的水解对这些抑制剂的敏感性远低于3-AABP和4-AABP，表明2-AABP是该酶的优先底物。小鼠的芳基酰胺水解活性对BNPP和BCPP均普遍不太敏感，这表明可能涉及一种不同于ES-3羧酸酯酶的酶。
