Seki H, Mizuno M, Satoh K, Nakabayashi M
Nihon Sanka Fujinka Gakkai Zasshi. 1987 Jun;39(6):905-10.
We investigated the conversion rate from arachidonic acid (A.A.) to PGI2 and the activity of PGI2 producing enzyme system in endothelial cells of umbilical veins (U.V.) and maternal omental veins (O.V.) in normal pregnancy (NOR) and toxemia of pregnancy (TOX). The conversion rate from A.A. to PGI2 for U.V. and O.V. in NOR was higher than that in TOX. There was a significant difference between NOR and TOX with the conversion rate for U.V. at a concentration of 172.4 nM/ml A.A. The apparent Vmax value for PGI2 producing enzyme system (nM/mg) in U.V. in NOR (n = 7) was 0.88 +/- 0.21 (mean +/- S.E.) and that for TOX (n = 3) was 1.63 +/- 0.18. The apparent Km value for the enzyme system (microM) in U.V. in NOR (n = 7) was 0.75 +/- 0.25, and that for TOX (n = 3) was 3.26 +/- 0.78. Significant differences (p less than 0.05) between NOR and TOX were observed with Vmax and Km values. The apparent Vmax value for the enzyme system in O.V. in NOR (n = 3) was 0.32 +/- 0.13, and that for TOX (n = 3) was 2.12 +/- 0.38. The apparent Km value for the enzyme system in O.V. of NOR (n = 3) was 0.26 +/- 0.06, and that for TOX (n = 3) was 0.97 +/- 0.09. There was a significant difference between (p less than 0.05) the Vmax and Km values for NOR and TOX. The present study showed that U.V. (fetal vessel) and O.V. (maternal vessel) in TOX had a lower activity PGI2 producing enzyme system than those in NOR due mainly to an imbalance between the substrate supply and cyclooxygenase activity.
我们研究了正常妊娠（NOR）和妊娠中毒症（TOX）中脐静脉（U.V.）和母体网膜静脉（O.V.）内皮细胞中花生四烯酸（A.A.）向前列环素（PGI2）的转化率以及PGI2产生酶系统的活性。NOR组中U.V.和O.V.从A.A.转化为PGI2的转化率高于TOX组。在A.A.浓度为172.4 nM/ml时，U.V.的转化率在NOR和TOX之间存在显著差异。NOR组（n = 7）中U.V.的PGI2产生酶系统的表观Vmax值（nM/mg）为0.88±0.21（平均值±标准误），TOX组（n = 3）为1.63±0.18。NOR组（n = 7）中U.V.的酶系统的表观Km值（μM）为0.75±0.25，TOX组（n = 3）为3.26±0.78。在Vmax和Km值方面，NOR和TOX之间存在显著差异（p＜0.05）。NOR组（n = 3）中O.V.的酶系统的表观Vmax值为0.32±0.13，TOX组（n = 3）为2.12±0.38。NOR组（n = 3）中O.V.的酶系统的表观Km值为0.26±0.06，TOX组（n = 3）为0.97±0.09。NOR和TOX的Vmax和Km值之间存在显著差异（p＜0.05）。本研究表明，TOX中的U.V.（胎儿血管）和O.V.（母体血管）的PGI2产生酶系统活性低于NOR中的，这主要是由于底物供应和环氧化酶活性之间的失衡。
