Effect of plasma from cyclic versus nutritionally induced anovulatory beef heifers on proliferation of granulosa cells in vitro.
The effect of plasma from cyclic versus nutritionally induced anovulatory beef heifers was evaluated on proliferation of bovine granulosa cells in vitro. Granulosa cells were obtained from small (1-5mm) follicles of cattle and cultured for 4 days. During the last 2 days of culture, cells were exposed to medium containing 0, 1 or 10% plasma from cyclic or anovulatory heifers in the presence or absence of IGF-I (100ng/ml). Cell numbers were determined. Regardless of source, increasing percentage of plasma to culture medium increased cell numbers. However, the plasma-induced increase was greater in granulosa cells exposed to cyclic heifer plasma versus anovulatory heifer plasma. In addition, concomitant treatment with IGF-I dramatically improved cell proliferation induced by anovulatory heifer plasma. These results indicate that plasma from cyclic heifers contain factors that are a greater stimulus to granulosa cell proliferation than plasma from anovulatory heifers. Systemic factors such as IGF-I may play a role in directly regulating granulosa cell proliferation in cattle.
Spicer
L J
LJ
Department of Animal Science, Oklahoma State University, Stillwater, OK 74078, United States. leon.spicer@okstate.edu
Bossis
I
I
Wettemann
R P
RP
D000818:Animals; D000858:Anovulation / Q000097:blood* / Q000209:etiology; D002417:Cattle / Q000097:blood*; D002455:Cell Division; D002478:Cells, Cultured; D003470:Culture Media; D004032:Diet; D030762:Estrous Cycle / Q000097:blood*; D005260:Female; D006107:Granulosa Cells / Q000166:cytology*; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D011994:Recombinant Proteins / Q000494:pharmacology
D003470:Culture Media; D011994:Recombinant Proteins; D007334:Insulin-Like Growth Factor I