Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.1.1.3 (HSD)
 3,464 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have previously shown a decrease in fetal zone-specific ACTH-stimulable dehydroepiandrosterone formation and an increase in definitive zone-specific cortisol biosynthesis in the baboon fetal adrenal gland in the second half of gestation. Therefore, the fetal and definitive zones seem to develop a divergence in functional capacity with advancing gestation. We have proposed, therefore, that there is a selective decrease in ACTH receptor expression and thus tropic responsivity to ACTH within the fetal zone in the second half of primate pregnancy. The present study examined this possibility and whether corresponding changes occurred in the developmental expression of major components required for steroidogenesis. ACTH receptor messenger RNA (mRNA) levels, determined by in situ hybridization, in the fetal zone of the baboon fetal adrenal were approximately 2-fold greater (P < 0.05) at mid (i.e. day 100) than at late (i.e. day 170) gestation and 3-fold greater (P < 0.01) in the definitive zone than in the fetal zone in late gestation (term = 184 days). Both ACTH receptor and low density lipoprotein receptor mRNA levels, determined by Northern blot in the whole fetal adrenal, also decreased (P < 0.001) by approximately 50%, whereas the mRNA levels for the definitive zone-specific delta5-3beta-hydroxysteroid dehydrogenase/isomerase (3beta-HSD) enzyme required for cortisol biosynthesis increased over 13-fold (P < 0.001) between mid and late gestation. In contrast, mRNA expression of the steroidogenic enzymes P-450 cholesterol side-chain cleavage and 17alpha-hydroxylase/17-20 lyase were unchanged throughout gestation. We conclude that the decrease in ACTH receptor mRNA expression and ACTH-stimulable dehydroepiandrosterone formation in the second half of gestation reflect a decline in functional capacity of the fetal zone, whereas the increase in 3beta-HSD mRNA expression and cortisol production results from the ACTH receptor-mediated development and enhanced functional capacity of the definitive zone.
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PMID:Decline in adrenocorticotropin receptor messenger ribonucleic acid expression in the baboon fetal adrenocortical zone in the second half of pregnancy. 907 25

Although progesterone plays an essential role in ovulation and the luteiniziation of the primate follicle, the expression of cellular components required for progesterone synthesis and their control is not well defined. This study was designed to determine the time course and gonadotrophin versus steroid regulation of the transcription of genes involved in progesterone synthesis in peri-ovulatory follicles. Granulosa cells or whole ovaries were obtained from macaques undergoing controlled ovarian stimulation either before (0 h) or up to 36 h following the administration of an ovulatory human chorionic gonadotrophin (HCG) bolus with or without a 3beta-hydroxysteroid dehydrogenase (3beta-HSD) inhibitor, with or without a non-metabolizable progestin. Granulosa cell concentrations of low density lipoprotein receptor (LDL-R) and steroidogenic acute regulatory protein (StAR) mRNA increased transiently 12 h following HCG administration (P < 0.05) at which time steroid depletion tended to reduce StAR mRNA (P = 0.06). At 36 h post-HCG progesterone suppressed the LDL-R mRNA levels (P < 0.05). P450 side-chain cleavage (P450scc) mRNA decreased in a time-dependent fashion up to 24 h, whereas 3beta-HSD mRNA increased within 12 h of HCG administration (P < 0.05) in a steroid-independent manner. Whole ovarian 17alpha-hydroxylase (P450c17) and granulosa cell P450 aromatase (P450arom) mRNA declined in a time-dependent fashion; by 36 h after HCG administration, steroid depletion increased P450arom mRNA, although progestin replacement did not return aromatase to control values (P < 0.05). These data demonstrate diverse patterns of steroidogenic enzyme expression that generally reflect the conversion of the macaque peri-ovulatory follicle from an oestrogen to progesterone producing gland. Although mRNAs associated with progesterone synthesis and metabolism are primarily regulated by gonadotrophins, cholesterol uptake and utilization may be modulated locally by steroids in luteinizing granulosa cells.
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PMID:Hormonal regulation of steroidogenic enzyme expression in granulosa cells during the peri-ovulatory interval in monkeys. 1061 Dec 55