These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Sex steroid and prostaglandin interactions upon the purified rat myometrial plasma membranes.
    Author: Deliconstantinos G, Fotiou S.
    Journal: Mol Cell Endocrinol; 1986 May; 45(2-3):149-56. PubMed ID: 3011559.
    Abstract:
    [14C]Estradiol, [14C]estrone, [14C]progesterone and [3H]prostaglandins (PGs) E2 and F2 alpha, when incubated with myometrial plasma membranes (MPM) at a concentration of 1 X 10(-6) M for 1 h at 37 degrees C, bind into MPM at pmolar concentrations. Unlabeled steroids inhibited [3H]PGE2 and [3H]PGF2 alpha binding to MPM in a dose-dependent manner. Membrane-bound and free steroids or PGs were found to be essentially unchanged under the present incubation conditions. Ca2+ ions up to 10 mM increased steroid binding into MPM. Molecular interactions between steroids and MPM were assessed by measuring the steady-state fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH), and by estimating the changes in the allosteric properties of MPM-bound (Na+ + K+)ATPase by fluoride (F-). Steroids appear to increase the MPM fluidity, evaluated through changes in the Hill coefficient for MPM-bound (Na+ + K+)ATPase by F- and by the fluorescence polarization method. Binding of sex steroids to MPM increased the membrane fluidity and decreased the binding of the uterus stimulatory PGs by membrane receptors. These studies provide a basis for postulating that a 'non-genomic' mechanism of sex steroids induces reduction of uterine contractions.
    [Abstract] [Full Text] [Related] [New Search]