Metabolism of prostaglandin E 2 in guinea pig liver.

The metabolism of prostaglandin E2 in a preparation of guinea pig liver was recently studied (1). One group of metabolites formed from PGEzl consisted of 1 la!, 15-dihydroxy-g-ketoprost- 5-enoic acid and llcr-hydroxy-9,15-diketoprost-5-enoic acid. These compounds have been isolated previously after incubation of PGE2 with guinea pig lung tissue (2). A second group of metabolites consisted of compounds belonging to the F series of prostaglandins. These metabolites were identified as PGFz,, 9a, 1 lar ,15-trihydroxyprost-5-enoic acid, and 9a, llor-dihy- droxy-15-ketoprost&enoic acid. A third group of metabolites consisted of 8-iso-PGEz and a compound tentatively identified as &so-PGF?,. The present paper describes results of experiments designed to elucidate the pathways by which the members of the first two groups of metabolites mentioned above are formed from PGE2. In the course of this investigation the absolute configuration of the alcohol group at C-15 of lla, 15-dihydroxy-9-ketoprost-5- enoic acid was determined.