Newly hatched chick ovarian cell subpopulations metabolize distinctively progestin and androgen precursors
Por:
Alvarez-Fernáandez G., Juárez-Oropeza M.A., Velázquez P., del Pliego M.G., Méndez-Herrera M.C., Pedernera E.
Publicada:
1 ene 1995
Resumen:
The aim of this study was to characterize the ability of four different cell fractions (F1, F2, F3, and F4), isolated from the ovary of newly hatched chick by means of subsequent metrizamide gradients (0-15%), to metabolize progestins and androgens. The results showed the presence of 17?- hydroxylase/C17-20 lyase and 3?-hydroxysteroid dehydrogenase/isomerase (3?- HSD) activities in the typical steroidogenic cells isolated in F1 (d = 1.012 g/ml). Primary oocytes present in F2 (d = 1.037 g/ml) did not show relevant steroid metabolism in the various assays that were carried out. Fractions 3 (d = 1.055 g/ml) and 4 (d = 1.071 g/ml), which contained a mixture of prefollicular and poorly differentiated epithelial cells, presented both 5?- reductase and aromatase activities, whereas 17?-HSD activity was mainly located in the cells of fraction 3. It is highly possible that poorly differentiated epithelial cells of fractions 3 and 4 are responsible for the steroidogenic activity. We conclude that in newly hatched chick ovary, typical steroidogenic cells metabolize progestins to androgens, and poorly differentiated epithelial cells further aromatize androgens to estrogens. In addition, we suggest the existence of at least two metabolically distinct poorly differentiated epithelial cell subpopulations, one presenting 5?- reductase and aromatase activities and another exhibiting 17?-HSD activity.
Filiaciones:
Alvarez-Fernáandez G.:
Departamento de Bioquímica, Departamento de Histología y Departamento de Embriología, Facultad de Medicina, Universidad Nacional Autónoma de México, México, 04510 D.F
Juárez-Oropeza M.A.:
Departamento de Bioquímica, Departamento de Histología y Departamento de Embriología, Facultad de Medicina, Universidad Nacional Autónoma de México, México, 04510 D.F
Velázquez P.:
Departamento de Bioquímica, Departamento de Histología y Departamento de Embriología, Facultad de Medicina, Universidad Nacional Autónoma de México, México, 04510 D.F
del Pliego M.G.:
Departamento de Bioquímica, Departamento de Histología y Departamento de Embriología, Facultad de Medicina, Universidad Nacional Autónoma de México, México, 04510 D.F
Méndez-Herrera M.C.:
Departamento de Bioquímica, Departamento de Histología y Departamento de Embriología, Facultad de Medicina, Universidad Nacional Autónoma de México, México, 04510 D.F
Pedernera E.:
Departamento de Bioquímica, Departamento de Histología y Departamento de Embriología, Facultad de Medicina, Universidad Nacional Autónoma de México, México, 04510 D.F
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