Demonstration of novel compounds in human fetal tissues and a consideration of their possible role in parturition.
A study of a new group of compounds and their possible relevance to human parturition is presented. These compounds behave chemically and chromatographically like steroids and have been tentatively identified as analogues of 11-hydroxypregnenolone. Determined by radioenzymatic assay, highest levels were found in the fetal zone of the fetal adrenal and were about 100 times those of fetal serum. Umbilical cord levels were higher after spontaneous labor than after elective cesarean section or induced labor in premature as well as mature infants. It is hypothesized that a fetal factor distinct from adrenocorticotropic hormone acts on the adrenal cortex, particularly the fetal zone, to stimulate 11 beta-hydroxylation of nonglucocorticoid corticosteroids and that these steroids and their metabolites are excreted via the urine into the amniotic fluid. Thus they would reach the membranes and decidua where they might complete with progesterone for receptor sites, decreasing lysosomal stability with the resultant production of prostaglandins and the onset of labor.
D015062:11-Hydroxycorticosteroids / Q000378:metabolism; D042842:11-beta-Hydroxysteroid Dehydrogenases; D006907:17-alpha-Hydroxypregnenolone / Q000031:analogs & derivatives* / Q000378:metabolism; D000302:Adrenal Cortex / Q000378:metabolism; D002850:Chromatography, Gel; D003348:Cortisone / Q000378:metabolism; D005260:Female; D005333:Fetus / Q000378:metabolism*; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism; D006913:Hydroxysteroid Dehydrogenases / Q000378:metabolism; D006914:Hydroxysteroids / Q000378:metabolism; D007231:Infant, Newborn; D007743:Labor, Obstetric; D011247:Pregnancy; D011863:Radioimmunoassay
D015062:11-Hydroxycorticosteroids; D006914:Hydroxysteroids; D006907:17-alpha-Hydroxypregnenolone; D006913:Hydroxysteroid Dehydrogenases; D042842:11-beta-Hydroxysteroid Dehydrogenases; D003348:Cortisone; D006854:Hydrocortisone