Identification of steroidogenic cell subpopulations in the ovary of the newly hatched chicken.
The aim of the present study is the isolation of subpopulations of steroid-producing cells in the ovary of the newly hatched chicken. Cells were obtained by fractional trypsin dissociation of the ovary and isopycnic separation in a continuous metrizamide gradient (0-30%). Testosterone and 17 beta-estradiol secretion was measured by radioimmunoassay in the incubation medium of the isolated cells. Six fractions of ovarian cells were studied. Fraction II (density 1.080) contained typical steroidogenic cells with a positive reaction for 3 beta-hydroxysteroid dehydrogenase, delta 5-isomerase. This fraction secreted testosterone (3.7 ng/10(6) cells/2 hr) but no 17 beta-estradiol secretion was detectable. The majority (85%) of cells obtained in fraction VI (density 1.150) were relatively undifferentiated and contained polyribosomes, mitochondria with lamellar cristae, and few rough endoplasmic reticulum; only 3-5% of the cells of this fraction were similar to those of fraction II. In fraction VI the highest level of 17 beta-estradiol secretion was found (2.9 ng/10(6) cells/2 hr) whereas testosterone was at a minimum level (0.06 ng/10(6) cells/2 hr). Results strongly suggest the existence of two cell subpopulations in the inmature chicken ovary: typical steroidogenic and poorly differentiated cells which secrete testosterone and 17 beta-estradiol, respectively.
Pedernera
E
E
Departamento de Embriología, Facultad de Medicina, Universidad Nacional Autónoma de México, DF 04510.
Gómez
Y
Y
Velázquez
P
P
Juárez-Oropeza
M A
MA
González del Pliego
M
M
D000818:Animals; D000831:Animals, Newborn; D002469:Cell Separation; D002645:Chickens / Q000378:metabolism*; D004958:Estradiol / Q000096:biosynthesis* / Q000378:metabolism; D005260:Female; D008854:Microscopy, Electron; D010053:Ovary / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D013739:Testosterone / Q000096:biosynthesis* / Q000378:metabolism
D013739:Testosterone; D004958:Estradiol