Jonsson C E, Tuvemo T, Hamberg M
Biol Neonate. 1976;29(3-4):162-70. doi: 10.1159/000240860.
The content of prostaglandins (PGs) in homogenates of arteries, connective tissue from human umbilical cords, and the capacity for biosynthesis of PGs in these tissues were studied. Lipid extracts were prepared and subjected to chromatography on silicic acid columns. PGs were eluted by ethyl acetate after elution with ethyl acetate-benzene (1:9) and determined by bioassay. For studies of the content of PGs, the cords were immediately frozen after delivery and homogenized in cold ethanol. Cords taken at vaginal deliveries contained amounts equivalent to approximately 700 ng prostaglandin E2/g dry weight and cords taken at caesarean sections about 450 ng/g. After homogenization and incubation of arteries in potassium phosphate buffer at 37 degrees C for 30 min the PG content increased from about 80 to 200 ng/g. Addition of arachidonic acid increased the biosynthesis fivefold. Indomethacin inhibited it. Most of the smooth muscle stimulating activity of the homogenated cords was due to prostaglandin E compounds, but smooth muscle stimulating material similar to prostaglandin F1alpha and F2alpha was also present. Prostaglandin E2 was conclusively identified by gas chromatography -- mass spectrometry. The findings are compatible with the view that local biosynthesis of PGs is very active in the human umbilical cord after delivery.
对动脉匀浆、人脐带结缔组织中前列腺素（PGs）的含量以及这些组织中PGs的生物合成能力进行了研究。制备脂质提取物并在硅酸柱上进行色谱分析。先用乙酸乙酯 - 苯（1:9）洗脱，再用乙酸乙酯洗脱PGs，然后通过生物测定法进行测定。为了研究PGs的含量，脐带在分娩后立即冷冻，并在冷乙醇中匀浆。经阴道分娩获取的脐带中PGs含量约相当于每克干重700 ng前列腺素E2，剖宫产获取的脐带中约为每克450 ng。动脉在37℃的磷酸钾缓冲液中匀浆并孵育30分钟后，PG含量从约80 ng/g增加到200 ng/g。添加花生四烯酸使生物合成增加了五倍。吲哚美辛抑制了这种增加。匀浆后的脐带大部分平滑肌刺激活性归因于前列腺素E类化合物，但也存在类似于前列腺素F1α和F2α的平滑肌刺激物质。通过气相色谱 - 质谱法最终鉴定出前列腺素E2。这些发现与分娩后人类脐带中PGs的局部生物合成非常活跃这一观点相符。
