Prostaglandin E antagonist activity of 11, 15-bisdeoxy prostaglandin E1 and congeners.

d,l-11, 15-bisdeoxy PGE1 and certain of its congeners were shown to inhibit gerbil colon contractions induced by l-PGE1. While some of these compounds were selectively antagonistic of PGE1-induced contractions, others additionally inhibited the gerbil colon agonist activities of l-PGE2alpha and acetylcholine. The PGE1 inhibitory activity was apparently competitive in nature. With relatively weak potencies, the bisdeoxy PGE congeners displaced 3H-PGE1 from a fat cell binding site, suggesting competition for a common, putative receptor. Structure-activity relationships and potential utility of these analogs are discussed.