Relaxation to oestrogen receptor subtype selective agonists in male and female mouse aorta

It has been reported that the oestrogen receptor (ER) alpha agonist 4,4,4-(4-propyl-[1H]-pyrazole- 1,3,5-triyl) tris-phenol (PPT) is more potent than the ER-beta receptor agonist 2,3-bis(4- hydroxyphenyl)-propionitrile (DPN) at producing relations in rat mesenteric artery. We have investigated the relaxant actions of the ER-alpha agonist PPT and the ER-beta agonist DPN in aorta from male and female mouse. Rings of blood vessel were set up in small vessel myographs for recording of isomeric contractions. Tissues were contracted with KCl (40 mM) and tested for relaxations to acetylcholine, then again contracted with KCl and tested for relaxations to increasing concentrations of ER agonists. In male and female mouse aorta, the ER-beta agonist DPN produced significantly greater relaxations than the ER-alpha agonist PPT.