Steroidal and growth factor regulation of [3H]thymidine incorporation by cultured endosalpingeal cells of the bovine oviduct

Summary Cultured cells from the bovine endosalpinx were used to evaluate effects of estradiol-17β, progesterone, epidermal growth factor, and insulinlike growth factors I and II on ³H]thymidine incorporation. Cells were treated with hormones and growth factors when approximately 50% confluent. After 24 h, DNA synthesis was quantified by pulsing cells with ³H]thymidine for 12 h and determining uptake into DNA. Cells prepared by mechanical dispersal incorporated more ³H]thymidine than cells dispersed with collagenase. However, hormonal responses were the same for both types of cells. As compared to plastic, cells on a Matrigel substratum exhibited lower incorporation of ³H]thymidine and were unresponsive to hormones. Estradiol-17β increased ³H]thymidine incorporation slightly at 10⁻¹⁰ mol/liter and higher. Epidermal growth factor, insulinlike growth factor-I, and insulinlike growth factor-II also stimulated ³H]thymidine incorporation. Effects of insulinlike growth factor-I were greater for cells treated with estradiol-17β. In the absence of estradiol, progesterone inhibited ³H]thymidine incorporation at 1, 10, and 100 ng/ml. When estradiol-17β was present, progesterone stimulated ³H]thymidine incorporation at 1 ng/ml and reduced incorporation at 100 ng/ml. In conclusion, ³H]thymidine incorporation by cultured oviductal endosalpingeal cells can be regulated by ovarian steroids and growth factors. These molecules may represent signals through which the ovary, embryo, and oviduct regulate oviductal growth. Work conducted while on a sabbatical leave supported by the Deutsche Forschungsgemeinschaft.