Metabolism of 8-iso-prostaglandin F2alpha.
Metabolism of 8-iso-prostaglandin F2alpha.
复制标题
8-异前列腺素 F2α 的代谢。
作者：
S. Basu
将氚标记（x=1.1 MBq/17.7 μ g/kg）和未标记的8-iso-PGF 2 α（43 μ g/kg）静脉内给予雌性家兔，并在4 h内频繁采集血液和连续尿液样本。总放射性迅速从循环中流失。约80%的总放射性在4小时内在尿液中发现。发现8-iso-PGF 2 α在分布相的血浆半衰期为1 min。终末消除相半衰期约为4 min。给药后1.5 min，血浆放射性的64%、19%和13%分别为8-iso-PGF 2 α、15-酮-8-iso-PGF 2 α和β-氧化产物。20分钟血浆的值分别为5%、2%和88%。10 min-4 h尿样的放射性色谱图主要为极性更强的β-氧化产物。α-四去甲-15-酮-13，14-二氢-8-iso-PGF 2 α被鉴定为主要的尿液代谢物，因此，8-iso-PGF 2 α在家兔体内主要通过C-15脱氢、δ 13-双键还原和β-氧化代谢为几种降解的极性代谢物，并有效地排泄到尿液中。
Tritium labelled (x=1.1 MBq/17.7 microg/kg) and unlabelled 8-iso-PGF2alpha (43 microg/kg) were administered intravenously to female rabbits and frequent blood and continuous urinary samples were collected up to 4 h. The total radioactivity was lost rapidly from the circulation. About 80% of the total radioactivity was found in urine within 4 h. The plasma half-life of 8-iso-PGF2alpha is found to be 1 min at the distribution phase. The terminal elimination phase half-life was about 4 min. At 1.5 min after administration 64%, 19% and 13% of the plasma radioactivity represented 8-iso-PGF2alpha, 15-keto-8-iso-PGF2alpha and beta-oxidised products, respectively. The values for 20-min plasma were 5%, 2%, and 88%. The radiochromatograms from 10 min-4 h urinary samples were dominated by more polar beta-oxidised products. Alpha-Tetranor-15-keto-13,14-dihydro-8-iso-PGF2alpha was identified as a major urinary metabolite.Thus, 8-iso-PGF2alpha metabolises in the rabbit mainly to several degraded polar metabolites through dehydrogenation at C-15, reduction of delta13-double bond and beta-oxidation, and excretes efficiently into the urine.