Oxytocin gene expression and action in bovine preovulatory follicles.
JE Fortune, AK Voss
Regul Pept | Published : 1993
We have studied oxytocin (OT) gene expression, secretion, and action in bovine preovulatory follicles during the follicular phase of the estrous cycle. OT is secreted in vitro by follicular granulosa cells, but not by theca cells. Both OT content of granulosa cells and their ability to secrete OT in culture increased dramatically when follicles were obtained after the gonadotropin surge (LH surge) that triggers ovulation. These changes were correlated with increased levels of messenger RNA (mRNA) for OT in granulosa cells obtained after vs. before the LH surge. When granulosa cells were obtained before the surge, both OT secretion and OT mRNA levels increased with time in culture, and the in..View full abstract