Regulation of aromatic oxidation of estradiol-17β in maternal hepatic, fetal hepatic and placental tissues: Comparative effects of a series of inducing agents
| Autor: | Moses J. Namkung, Sidney D. Nelson, David J. Porubek, Mont R. Juchau |
|---|---|
| Rok vydání: | 1985 |
| Předmět: |
Male
Pregnenolone Carbonitrile Aroclors medicine.medical_specialty Polychlorinated Dibenzodioxins medicine.drug_class Placenta Biology beta-Naphthoflavone Biochemistry Hydroxylation chemistry.chemical_compound Endocrinology Pregnancy Safrole Internal medicine Cytochrome P-450 CYP1A1 medicine Animals Benzoflavones Fetus Estradiol Ethanol Rats Inbred Strains Chlorodiphenyl (54% Chlorine) Rats Liver chemistry Estrogen Isosafrole Phenobarbital Steroid Hydroxylases Methylcholanthrene Pregnenolone Female medicine.drug |
| Zdroj: | Journal of Steroid Biochemistry. 22:563-567 |
| ISSN: | 0022-4731 |
| DOI: | 10.1016/0022-4731(85)90179-7 |
| Popis: | The effects of nine separate inducers of cytochrome P-450-dependent monooxygenases on the hydroxylation of estradiol-17 beta (E2) were investigated in near-term pregnant rats. Isosafrole exhibited highly effective inducing properties in the maternal liver (20-fold and 5-fold increases in 4- and 2-hydroxylase activities respectively). Pregnenolone 16 alpha-carbonitrile produced approx 20- and 30-fold increases in measured respective rates of 4- and 2-hydroxylase activities in fetal hepatic tissues; isosafrole produced only 2-fold increases in the same reaction. Only minor changes or slight increases in estrogen hydroxylation rates were observed in maternal hepatic, fetal hepatic or placental tissues following treatment with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or other potent 3-methylcholanthrene (MC)-like inducing agents (beta-naphthoflavone, MC, caffeine). Phenobarbital exhibited relatively weak inducing properties and exposure of pregnant rats to ethanol from days 3-19 of gestation was without statistically significant effects on the parameters investigated. Rat placentas exhibited extremely low estrogen hydroxylase activities irrespective of pre-exposure of pregnant rats to the inducers studied. The results suggested separate regulatory controls for estrogen 2- and 4-monooxygenase activities even though relatively high correlation between the two reaction were generally observed in all three tissues. |
| Databáze: | OpenAIRE |
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