Previous work from our laboratory has demonstrated that major histocompatibility complex (MHC) antigens are expressed on cultured bovine luteal cells following exposure to the T lymphocyte-derived cytokine, interferon-gamma (IFN-γ). In light of these actions of IFN-γ, it was of interest to investigate the effects of this cytokine on other aspects of luteal function. Therefore, bovine luteal cells were cultured for 7 days in the presence or absence of IFN-γ, and luteal progesterone (P4), prostaglandin F(2α) (PGF(2α)), and 6-keto-prostaglandin F(1α) (6-keto-PGF(1α)) production were evaluated. After a 24-h exposure to IFN-γ (100 U), both PGF(2α) and 6-keto-PGF(1α) production were decreased approximately 50% (p < 0.05). However, as time in culture progressed, IFN-γ markedly increased the synthesis of both prostaglandins approximately 400% above controls (p < 0.05). Stimulation of prostaglandin production by IFN-γ was abrogated by the addition of exogenous P4. During the period of IFN-γ-stimulated prostaglandin synthesis, LH-stimulated P4 production was inhibited by IFN-γ treatment. However, the suppression of P4 production by IFN-γ was not mediated by the increase in prostaglandins since concomitant treatment with indomethacin did not reverse the inhibition of steroidogenesis. These results suggest that IFN-γ, in addition to an indirect role in promoting immune response mechanisms, may also directly affect luteal function by enhancing luteal prostaglandin synthesis and by inhibiting luteal steroidogenesis.
All Science Journal Classification (ASJC) codes
- Cell Biology
- Developmental Biology