Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0728731 (prematurity)
 7,134 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Changes in circulating steroid hormones, the incidence of myometrial contractions, and the onset of labour were all monitored after administration of the 3 beta-hydroxysteroid dehydrogenase inhibitor, epostane, to chronically catheterized ewes and fetuses near term. In all animals the drug induced delivery 33-36 h after injection or infusion into the ewe with the birth of live healthy lambs which showed normal subsequent development. Epostane induced immediate, permanent falls in both maternal and fetal plasma progesterone concentrations, accompanied by increased PGF metabolite concentrations in the uterine vein beginning 15 min after treatment. Of the other hormonal changes observed, the most striking was the pronounced drop in both maternal and fetal plasma cortisol. In the fetus this fall was followed by increasing concentrations of circulating ACTH which eventually restored the cortisol levels. By 12-24 h after epostane a substantial overshoot had occurred and at 27-30 h the fetal plasma cortisol concentrations were as high as those seen during normal parturition at term. No significant changes in maternal plasma oestradiol-17 beta could be detected after epostane treatment or during labour. The incidence of slow myometrial contractions increased significantly during the second 3-h period after epostane, although their duration did not change. Contraction patterns typical of first stage labour were seen from 20 to 24 h. These results show that epostane may be used as a safe, predictable inducing agent in sheep if given 6-10 days before term; the lambs showed no signs of prematurity despite their lowered plasma cortisol concentrations which persisted for some hours before labour was induced.
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PMID:Effects on maternal and fetal steroid concentrations of induction of parturition in the sheep by inhibition of 3 beta-hydroxysteroid dehydrogenase. 283 51

Adrenal steroidogenesis was evaluated in 25 sick premature infants with a gestational age of less than 30 weeks. ACTH stimulation tests were performed on the fourth day of life using synthetic ACTH (36 micrograms/kg). Considering the stress and degree of illness, preterm newborns had low basal cortisol levels (mean +/- SEM, 207.4 +/- 23.5 nmol/L), and their levels were similar to basal levels reported for healthy full-term newborns (170.7 +/- 26.8 nmol/L; P = 0.31; reference data from Endocrine Sciences, Inc., Calabasas Hills, CA). However, compared to term neonates, preterm infants had markedly elevated basal levels of 17-hydroxypregnenolone (54.3 +/- 11.2 nmol/L), 17-hydroxyprogesterone (19.7 +/- 4.0 nmol/L), and 11-deoxycortisol (19.1 +/- 3.3 nmol/L), which were 7-, 18-, and 8-fold higher, respectively, than values for term infants. The activity of 3 beta-hydroxysteroid dehydrogenase was not significantly reduced in extremely premature neonates (mean basal ratio of 17-hydroxypregnenolone/17-hydroxyprogesterone, 2.9 +/- 0.2; ACTH-stimulated ratio, 6.5 +/- 0.4). In contrast, the mean basal substrate/product ratio of 11-deoxycortisol was markedly elevated in the preterm infants (11.9 +/- 2.2, ratio x 10(-2) compared to that in the full-term infants (2.1 +/- 0.4, ratio x 10(-2); P < 0.001). These findings are consistent with decreased activity of 11 beta-hydroxylase (11 beta OH) in preterm infants born at less than 30 weeks gestation. Decreased 11 beta OH activity appears to be more prominent than the deficiency of 3 beta-hydroxysteroid dehydrogenase that has been found in infants with lesser degrees of prematurity, suggesting that 11 beta OH activity may be regulated during fetal development to increase during the latter part of gestation.
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PMID:Adrenal steroidogenesis in very low birth weight preterm infants. 810 10