Possible evidence that dehydroepiandrosterone sulfate (DHA-S) stimulates cervical ripening by a membrane-mediated process: Specific binding-sites in plasma membrane from human uterine cervix

Journal Article · Mon Apr 01 00:00:00 EST 1991 · Research Communications in Chemical Pathology and Pharmacology; (United States)

OSTI ID:5556845

Ohno, T; Imai, A; Tamaya, T ^[1]

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1. Department of Obstetrics and Gynecology, Gifu University School of Medicine (Japan)

Fetal adrenal steroid, dehydroepiandrosterone sulfate (DHA-S) is well known to promote cervical ripening in late pregnancy. The presence of sites specifically binding the DHA-S in plasma membrane was studied in human cervical fibroblasts prepared from pregnant uterus. The fibroblasts were incubated with {sup 3}H DHA-S and then fractionated into plasma membranes, cytosol, nuclei, and other organella debris. The specific activity of 3H-count in the plasma membrane fraction was enriched {approximately} 7-fold compared with the whole homogenate. When the isolated plasma membrane preparations from the fibroblasts were exposed to {sup 3}H DHA-S, the binding showed saturation kinetics; an apparent equilibrium dissociation constant (Kd) of 12 nM, and the binding capacity (Bmax) of 1.25 pmol/mg protein. The present results suggest that DHA is bound to and recognized by components in plasma membrane, and may exert its action on cervical ripening through the membrane-mediated processes.

• OSTI ID: 5556845
• Journal Information: Research Communications in Chemical Pathology and Pharmacology; (United States), Vol. 72:1; ISSN 0034-5164
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ANDROSTERONE
BIOCHEMICAL REACTION KINETICS
UTERUS
BIOCHEMISTRY
CELL MEMBRANES
FIBROBLASTS
IN VITRO
MAN
PREGNANCY
RECEPTORS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ANDROGENS
ANDROSTANES
ANIMAL CELLS
ANIMALS
BODY
CELL CONSTITUENTS
CHEMISTRY
CONNECTIVE TISSUE CELLS
FEMALE GENITALS
HORMONES
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
KETONES
KINETICS
MAMMALS
MEMBRANE PROTEINS
MEMBRANES
ORGANIC COMPOUNDS
ORGANS
PRIMATES
PROTEINS
REACTION KINETICS
SOMATIC CELLS
STEROID HORMONES
STEROIDS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques