The relationship between ovarian steroids and uterine estrogen receptors during late pregnancy

Journal Article · Tue Jan 01 00:00:00 EST 1991 · Life Sciences; (United States)

DOI:https://doi.org/10.1016/0024-3205(91)90016-5· OSTI ID:5317282

Cathey, T M; Chung, Kyung W ^[1]

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1. Univ. of Oklahoma, Oklahoma City (USA)

Although a direct interdependence exists between the ovarian steroids, estrogen and progesterone, the exact role of these two hormones during pregnancy, especially late pregnancy, is not completely understood. Investigations have been conducted to determine whether the circulating levels of progesterone and estrogen or changes in the ratio of progesterone/estrogen in relation to the concentration of uterine estrogen receptors are associated with triggering parturition. Ninety-day old female rats were sacrificed at gestation days 14, 16, 18, 20 and two days post-partum. The plasma levels of estradiol and progesterone were measured by solid-phase radioimmunoassay. Uterine cytosol was subjected to a charcoal binding assay to determine the concentration of estrogen receptors. Our findings demonstrate that there is a significant drop in both plasma progesterone and estradiol during late pregnancy. Also indicated is a significant increase in uterine estrogen receptors throughout late pregnancy. Finally, during this period there is a direct correlation between the shift in the progesterone/estrogen ratio and the increase in the concentration of uterine estrogen receptors in late pregnancy.

• OSTI ID: 5317282
• Journal Information: Life Sciences; (United States), Vol. 49:4; ISSN 0024-3205
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ESTROGENS
BIOLOGICAL FUNCTIONS
RECEPTORS
PROGESTERONE
BIOCHEMICAL REACTION KINETICS
OVARIES
PREGNANCY
RADIOIMMUNOASSAY
RATS
UTERUS
ANIMALS
BIOASSAY
BODY
DIAGNOSTIC TECHNIQUES
FEMALE GENITALS
GONADS
HORMONES
IMMUNOASSAY
IMMUNOLOGY
ISOTOPE APPLICATIONS
KETONES
KINETICS
MAMMALS
MEMBRANE PROTEINS
ORGANIC COMPOUNDS
ORGANS
PREGNANES
PROTEINS
RADIOASSAY
RADIOIMMUNODETECTION
RADIOIMMUNOLOGY
REACTION KINETICS
RODENTS
STEROID HORMONES
STEROIDS
TRACER TECHNIQUES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques