Estradiol and luteinizing hormone regulation of insulin-like growth factor binding protein production by bovine granulosa and thecal cells.
To determine the effects of estradiol and luteinizing hormone (LH) on insulin-like growth factor-binding protein (IGFBP) production by bovine granulosa and thecal cells, both cell types were collected and cultured in serum-free medium with various hormone treatments, arranged in three experiments. In thecal cells, insulin stimulated (p < 0.05) production of IGFBP-2 and IGFBP-5, but had no effect (p > 0.10) on IGFBP-3 and IGFBP-4 production; LH stimulated (p < 0.05) production of IGFBP-2 and IGFBP-3 but had no effect (p > 0.05) on IGFBP-4 and IGFBP-5. Estradiol had no effect (p > 0.10) on IGFBP-2, IGFBP-3, IGFBP-4, and IGFBP-5 production by thecal cells. Production of IGFBP-2/-5 by granulosa cells from small follicles was inhibited (p < 0.05) by insulin, but estradiol and LH did not influence (p > 0.10) insulin's inhibitory effect on basal IGFBP-2/-5 production. Insulin, LH, and estradiol each inhibited IGFBP-4 production by small-follicle granulosa cells, but their effects were not additive. IGFBP-3 was not produced by small-follicle granulosa cells. In large-follicle granulosa cells, insulin and LH inhibited (p < 0.05) production of IGFBP-2/-5 and IGFBP-3, whereas estradiol had no effect. Insulin alone had no effect (p > 0.10) on production of IGFBP-4, but estradiol and LH inhibited (p < 0.05) production by large-follicle granulosa cells, and their effects were not additive. These results suggest that production of IGFBP-2, IGFBP-3, IGFBP-4, and IGFBP-5 by granulosa and thecal cells is differentially affected by hormonal stimuli.
Spicer
Leon J
LJ
Department of Animal Science, Oklahoma State University, Stillwater 74078, USA. igf1Leo@okstate.edu
Chamberlain
Connie S
CS
D000818:Animals; D002417:Cattle; D002452:Cell Count; D048429:Cell Size / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D003470:Culture Media; D004591:Electrophoresis, Polyacrylamide Gel; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D006107:Granulosa Cells / Q000187:drug effects / Q000378:metabolism*; D007004:Hypoglycemic Agents / Q000494:pharmacology; D007202:Indicators and Reagents; D007328:Insulin / Q000494:pharmacology; D018969:Insulin-Like Growth Factor Binding Proteins / Q000096:biosynthesis*; D008024:Ligands; D007986:Luteinizing Hormone / Q000494:pharmacology*; D013799:Theca Cells / Q000187:drug effects / Q000378:metabolism*
D003470:Culture Media; D007004:Hypoglycemic Agents; D007202:Indicators and Reagents; D007328:Insulin; D018969:Insulin-Like Growth Factor Binding Proteins; D008024:Ligands; D004958:Estradiol; D007986:Luteinizing Hormone