Transuteroplacental metabolism of cortisol and cortisone during mid- and late gestation in the baboon

Journal Article · Thu Nov 01 04:00:00 EST 1984 · Endocrinology; (United States)

DOI:https://doi.org/10.1210/endo-115-5-1946· OSTI ID:5886345

Pepe, G J; Albrecht, E D

We measured uterine extraction (i.e. metabolism) and transuteroplacental interconversion of cortisol (F) and cortisone (E) to determine whether metabolism across the uterus changes during pregnancy and contributes to the MCR of these corticosteroids. On day 100 (n . 4) or 170 (n . 3) of pregnancy (term . day 184), baboons (Papio anubis; 14-18 kg) were sedated with ketamine, and a constant infusion (0.38 ml/min) of 8-12 microCi (/sup 3/H)F and 9-15 microCi (/sup 14/C)E in 80 ml 0.9% NaCl-1% ethanol was initiated (time zero) via a maternal antecubital vein. At 60 min, animals were laparotomized, and at 70, 80, and 90 min, blood samples were obtained from right and left uterine veins and from a maternal saphenous vein. At 95 min, a transverse incision was made in the uterus, the fetus was isolated, and blood samples were obtained from the umbilical vein and artery. The cord was then clamped, and the fetus was delivered. Radio-labeled F and E were extracted from serum and purified by sequential paper chromatography, and metabolic parameters were calculated. Endogenous F and E levels were determined by RIA. In the mother, the percent conversions of E to F at midgestation (mean +/- SE; 72 +/- 4) and late gestation (65 +/- 3) were similar and exceeded (P less than 0.01) respective values for oxidation of F to E (51 +/- 7 and 46 +/- 7, respectively), indicating that maternal corticosteroid metabolism favors F formation and is unchanged during the second half of gestation. In contrast, corticosteroid metabolism across the uterus and placenta (transuteroplacental) was altered during pregnancy. At midgestation, transuteroplacental conversion of E to F (37 +/- 9) exceeded (P less than 0.05) the reverse reaction (18 +/- 3), whereas oxidation of F to E at term (28 +/- 4) was 7-fold greater (P less than 0.05) than reduction of E to F (4 +/- 1).

• Research Organization: Eastern Virginia Medical School, Norfolk
• OSTI ID: 5886345
• Journal Information: Endocrinology; (United States), Journal Name: Endocrinology; (United States) Vol. 115:5; ISSN ENDOA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADRENAL HORMONES
ANIMALS
APES
BIOLOGICAL MATERIALS
BLOOD
BODY
BODY FLUIDS
CARBON 14 COMPOUNDS
CORTICOSTEROIDS
CORTISONE
FEMALE GENITALS
FETAL MEMBRANES
FETUSES
GLUCOCORTICOIDS
HORMONES
HYDROCORTISONE
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
KETONES
LABELLED COMPOUNDS
MAMMALS
MATERIALS
MEMBRANE TRANSPORT
MEMBRANES
METABOLISM
ORGANIC COMPOUNDS
ORGANS
PLACENTA
PREGNANCY
PREGNANES
PRIMATES
STEROID HORMONES
STEROIDS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
UTERUS
VERTEBRATES