Pace-Asciak C R, Domazet Z
Biochim Biophys Acta. 1984 Nov 14;796(2):129-35. doi: 10.1016/0005-2760(84)90339-4.
15-Keto-13,14-dihydro 6-ketoprostaglandin E1 was positively identified by gas chromatography-mass spectrometry with negative-ion chemical ionisation detection from samples of rat kidney high-speed supernatant incubated with prostaglandin I2 in the presence of NAD+. A decreased formation of this product was observed when NAD+ was substituted with NADP+ and none was observed in the absence of nucleotide or substrate prostaglandin I2. Experiments with [9 beta-3H]prostaglandin I2 showed a time- and concentration-dependent loss of tritium which appeared as tritiated water, typical of reaction of [9 beta-3H]prostaglandin substrates with the enzyme, 9-hydroxyprostaglandin dehydrogenase. Time-course measurements of the appearance of tritiated water showed similar rates with 6-keto[9 beta-3H]prostaglandin F1 alpha and 15-keto-13,14-dihydro 6-keto[9 beta-3H]prostaglandin F1 alpha as substrates. These experiments suggest that the transformation of prostaglandin I2 and 6-ketoprostaglandin F1 alpha into the 15-keto-13,14-dihydro 6-ketoprostaglandin E1 catabolite occurs in this in vitro preparation via the corresponding 15-keto-13,14-dihydro catabolite of 6-ketoprostaglandin F1 alpha.
通过气相色谱 - 质谱联用仪的负离子化学电离检测，在NAD⁺存在的情况下，用前列腺素I₂孵育大鼠肾脏高速上清液样品，从而对15 - 酮基 - 13,14 - 二氢6 - 酮基前列腺素E₁进行了阳性鉴定。当用NADP⁺替代NAD⁺时，观察到该产物的形成减少，而在没有核苷酸或底物前列腺素I₂的情况下未观察到该产物的形成。用[9β - ³H]前列腺素I₂进行的实验表明，氚随时间和浓度依赖性损失，以氚化水的形式出现，这是[9β - ³H]前列腺素底物与9 - 羟基前列腺素脱氢酶反应的典型特征。以6 - 酮基[9β - ³H]前列腺素F₁α和15 - 酮基 - 13,14 - 二氢6 - 酮基[9β - ³H]前列腺素F₁α为底物，对氚化水出现的时间进程测量显示出相似的速率。这些实验表明，在这种体外制备中，前列腺素I₂和6 - 酮基前列腺素F₁α通过6 - 酮基前列腺素F₁α相应的15 - 酮基 - 13,14 - 二氢代谢物转化为15 - 酮基 - 13,14 - 二氢6 - 酮基前列腺素E₁代谢物。
