Greatly elevated and sustained secretion of oxytocin by bovine granulosa cells in serum‐free culture

Publisher Website
Google Scholar
Abstract
Bovine granulosa cells were cultured in collagen (Vitrogen 100)‐pretreated wells using defined medium to study the secretion of oxytocin and progesterone under serum‐free conditions. Secretion of oxytocin began spontaneously after the first day and was maintained at a high level during a 1 week culture period. Addition of serum to the medium reduced oxytocin concentrations by up to 90%. There were positive exponential relationships between oxytocin and progesterone concentrations and the inoculated cell density (range, 1.67 to 23.4 × 105 cells/ml/well). The results indicate that neither serum nor gonadotrophins are required for in vitro differentiation of bovine granulosa cells and that addition of serum may attenuate subsequent hormone secretion. This culture system should provide a better in vitro model for the study of ovarian oxytocin secretion than those previously described.