Abstract
Glycyrrhetic acid inhibits the metabolism of pro-gesterone and 11-deoxy-corticosterone by rat-liver homogenate; methyl vinyl ketone and p-benzoquinone inhibit the metabolism of progesterone. Glycyrrhetic acid inhibited progesterone metabolism by reduced triphosphopyridine nucleotide with a dialyzed supernatant, free from citrate, cis-aconitrate or iso-citrate. These results, and clinical results with glycyrrhetic acid and its analogs, are discussed.