A VASODEPRESSOR SUBSTANCE OF HUMAN PLACENTA

The authors of this article have been able to isolate from the human placenta large amounts of a vasodepressor substance able to cause relaxation of the duodenum, and decrease blood pressure in rats. The vasoactive substance was obtained only by extraction with dichloroacetic acid, hydrochloric acid, and with methylene chloride, but not with aqueous extract, or by ether, ethanol, or acetone extraction. The substance is not a peptide; it may be either a prostaglandin such as PGE1, or may be related to this group. Normal placenta usually yield more vasodepressor material than toxemic placenta.