Biomaterial Database

Cholesterol side-chain cleavage activity in rat fetal gonads: a limiting step for ovarian steroidogenesis. 1990

V Rouiller, and M N Gangnerau, and J L Vayssiere, and R Picon

Laboratoire de Physiologie du Développement, CNRS, URA 307, Université Paris 7, France.

The aim of this study was to examine the first step in steroidogenesis in male and female gonads of fetal rats. Pregnenolone production was measured by radioimmunoassay in organ culture, conversion of [3H]cholesterol to [3H]pregnenolone was evaluated in isolated mitochondria and cytochrome P-450scc was revealed by immunoblotting and immunocytochemical techniques. Our results clearly showed that in fetal testes (1) pregnenolone was produced in media where testes were cultured in the presence of trilostane and spironolactone, indicating an important metabolism of pregnenolone, (2) [3H]cholesterol was converted into [3H]pregnenolone in mitochondria, (3) cytochrome P-450scc was revealed in immunoblots with a molecular weight of 50,000, (4) cytochrome P-450scc was localized in Leydig cells from 15.5-day-old fetal testes onwards. With respect to fetal ovaries, we were unable to detect any scc activity, except after treatment with dibutyryl cyclic AMP. A lag period of 18 h was necessary to induce pregnenolone synthesis. However, the immunoperoxidase staining did not localize ovarian positive cells. Cytochrome P-450scc could be revealed in postnatal ovaries by immunoblotting and some interstitial positive cells were observed with immunostaining; the reaction was enhanced in luteinizing hormone-pretreated ovaries. These data indicate that (a) the cholesterol scc activity is present in fetal testes, (b) the conversion of cholesterol to pregnenolone is a limiting step for steroidogenesis in fetal ovaries. The inductive effect of the nucleotide on the enzyme suggests that the absence of gonadotrophic receptors in fetal female gonads could explain the lack of steroidogenesis before birth.(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
D007124	Immunoenzyme Techniques	Immunologic techniques based on the use of: (1) enzyme-antibody conjugates; (2) enzyme-antigen conjugates; (3) antienzyme antibody followed by its homologous enzyme; or (4) enzyme-antienzyme complexes. These are used histologically for visualizing or labeling tissue specimens.	Antibody Enzyme Technique, Unlabeled,Enzyme Immunoassay,Enzyme-Labeled Antibody Technique,Immunoassay, Enzyme,Immunoperoxidase Techniques,Peroxidase-Antiperoxidase Complex Technique,Peroxidase-Labeled Antibody Technique,Antibody Enzyme Technic, Unlabeled,Enzyme-Labeled Antibody Technic,Immunoenzyme Technics,Immunoperoxidase Technics,Peroxidase-Antiperoxidase Complex Technic,Peroxidase-Labeled Antibody Technic,Antibody Technic, Enzyme-Labeled,Antibody Technic, Peroxidase-Labeled,Antibody Technics, Enzyme-Labeled,Antibody Technics, Peroxidase-Labeled,Antibody Technique, Enzyme-Labeled,Antibody Technique, Peroxidase-Labeled,Antibody Techniques, Enzyme-Labeled,Antibody Techniques, Peroxidase-Labeled,Enzyme Immunoassays,Enzyme Labeled Antibody Technic,Enzyme Labeled Antibody Technique,Enzyme-Labeled Antibody Technics,Enzyme-Labeled Antibody Techniques,Immunoassays, Enzyme,Immunoenzyme Technic,Immunoenzyme Technique,Immunoperoxidase Technic,Immunoperoxidase Technique,Peroxidase Antiperoxidase Complex Technic,Peroxidase Antiperoxidase Complex Technique,Peroxidase Labeled Antibody Technic,Peroxidase Labeled Antibody Technique,Peroxidase-Antiperoxidase Complex Technics,Peroxidase-Antiperoxidase Complex Techniques,Peroxidase-Labeled Antibody Technics,Peroxidase-Labeled Antibody Techniques,Technic, Enzyme-Labeled Antibody,Technic, Immunoenzyme,Technic, Immunoperoxidase,Technic, Peroxidase-Antiperoxidase Complex,Technic, Peroxidase-Labeled Antibody,Technics, Enzyme-Labeled Antibody,Technics, Immunoenzyme,Technics, Immunoperoxidase,Technics, Peroxidase-Antiperoxidase Complex,Technics, Peroxidase-Labeled Antibody,Technique, Enzyme-Labeled Antibody,Technique, Immunoenzyme,Technique, Immunoperoxidase,Technique, Peroxidase-Antiperoxidase Complex,Technique, Peroxidase-Labeled Antibody,Techniques, Enzyme-Labeled Antibody,Techniques, Immunoenzyme,Techniques, Immunoperoxidase,Techniques, Peroxidase-Antiperoxidase Complex,Techniques, Peroxidase-Labeled Antibody
D007985	Leydig Cells	Steroid-producing cells in the interstitial tissue of the TESTIS. They are under the regulation of PITUITARY HORMONES; LUTEINIZING HORMONE; or interstitial cell-stimulating hormone. TESTOSTERONE is the major androgen (ANDROGENS) produced.	Interstitial Cells, Testicular,Leydig Cell,Testicular Interstitial Cell,Testicular Interstitial Cells,Cell, Leydig,Cell, Testicular Interstitial,Cells, Leydig,Cells, Testicular Interstitial,Interstitial Cell, Testicular
D008297	Male		Males
D008928	Mitochondria	Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)	Mitochondrial Contraction,Mitochondrion,Contraction, Mitochondrial,Contractions, Mitochondrial,Mitochondrial Contractions
D009924	Organ Culture Techniques	A technique for maintenance or growth of animal organs in vitro. It refers to three-dimensional cultures of undisaggregated tissue retaining some or all of the histological features of the tissue in vivo. (Freshney, Culture of Animal Cells, 3d ed, p1)	Organ Culture,Culture Technique, Organ,Culture Techniques, Organ,Organ Culture Technique,Organ Cultures
D010053	Ovary	The reproductive organ (GONADS) in female animals. In vertebrates, the ovary contains two functional parts: the OVARIAN FOLLICLE for the production of female germ cells (OOGENESIS); and the endocrine cells (GRANULOSA CELLS; THECA CELLS; and LUTEAL CELLS) for the production of ESTROGENS and PROGESTERONE.	Ovaries
D011284	Pregnenolone	A 21-carbon steroid, derived from CHOLESTEROL and found in steroid hormone-producing tissues. Pregnenolone is the precursor to GONADAL STEROID HORMONES and the adrenal CORTICOSTEROIDS.	5-Pregnen-3-beta-ol-20-one,5 Pregnen 3 beta ol 20 one
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D002784	Cholesterol	The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.	Epicholesterol
D002786	Cholesterol Side-Chain Cleavage Enzyme	A mitochondrial cytochrome P450 enzyme that catalyzes the side-chain cleavage of C27 cholesterol to C21 pregnenolone in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP11A1 gene, catalyzes the breakage between C20 and C22 which is the initial and rate-limiting step in the biosynthesis of various gonadal and adrenal steroid hormones.	CYP11A1,Cholesterol Desmolase,Cholesterol Monooxygenase (Side-Chain-Cleaving),Cytochrome P-450 CYP11A1,Cytochrome P-450(scc),20,22-Desmolase,CYP 11A1,Cytochrome P450 11A1,Cytochrome P450scc,20,22 Desmolase,Cholesterol Side Chain Cleavage Enzyme,Cytochrome P 450 CYP11A1