Abstract

To explore the immunological regulatory mechanisms of interferon-gamma (IFN-γ) on insulin-like growth factor 1(IGF-1) and its effect on pregnancy, the dynamic expression of mRNA and cellular localization of IGF-1 protein in the early pregnant (Day 9) rats after the injection of different doses of IFN-γ, their ovaries and uterus were collected and processed by RT-PCR and immunohistochemistry. ELISA assay was also applied to investigate the effect of exogenous IFN-γ on the level of IGF-1 in the peripheral blood. The results indicate that both uterine and ovarian IGF-1 mRNAs and IGF-1 immunoreactivity were the highest in the normal saline group and the lowest in the 300IU IFN-γ group (P < 0.01). When compared with the normal saline group, the IGF-1 expression was also lower in the 100IU IFN-γ-treated group (P < 0.05). The level of IGF-1 in peripheral blood of the 300IU IFN-γ group was the lowest, which was significantly different from normal saline group (P < 0.01) and 100IU IFN-γ group (P < 0.05), respectively. The results suggest that exogenous IFN-γ might regulate pregnancy by controlling the expression of IGF-1 in the uterus and ovaries in early pregnancy.

Key words: Insulin-like growth factor 1(IGF-1), interferon-gamma (IFN-γ), uterus, ovaries, early pregnant rats.

Abbreviation

IGF-1, Insulin-like growth factor 1; IFN-γ, interferon-gamma; D9, pregnant on the 9^th day; MHCII, major histocompatibility complex class II.