title: Progesterone interferes with the actions of prostaglandin (PG) E1 but not those of PGE2 or PGF2 alpha in a rat vascular preparation.
abstract: In the mammary gland some actions of prolactin seem mediated by PGs. Progesterone blocks several of the mammary effects of prolactin. We therefore investigated the effects of 100 ng/ml progesterone (within the normal human plasma concentration in pregnancy) on the vascular effects of PGE2, PGEF2 alpha and PGE1. Progesterone had no effects on the responses to PGE2 and PGF2 alpha but significantly (p less than 0.01) attenuated the actions of low concentrations of PGE1. It may have enhanced the actions of high PGE1 concentrations. Progesterone appears able to block some effects of PGE1 and to imitate others.
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects; D009638:Norepinephrine / Q000494:pharmacology; D011374:Progesterone / Q000494:pharmacology*; D011458:Prostaglandins E / Q000494:pharmacology*; D011460:Prostaglandins F / Q000494:pharmacology*; D051381:Rats
chemical_list: D011458:Prostaglandins E; D011460:Prostaglandins F; D011374:Progesterone; D009638:Norepinephrine