Transcriptomic analysis of the porcine anterior pituitary gland during the peri-implantation period.

The peri-implantation period is controlled by signals originating from hypothalamic-pituitary-ovarian axis, uterus and developing embryos. The transcriptomic activity of the anterior pituitary gland may be important for the control of the peri-implantation period. The aim of this study was to determine the alternations in the transcriptomic profile of porcine anterior pituitary gland during the peri-implantation period (days 15-16 of pregnancy) in comparison with established for the respective days of the oestrous cycle. Analysis using a microarray approach indicated that the 651 genes (fold-change ˂1.2; p ≤ .05) were differentially expressed (DEGs) in the anterior pituitary of pigs during the peri-implantation period when compared to cyclic females. Of these DEGs, 404 were upregulated and 247 downregulated. Analysis of occurred relationships among DEGs revealed that some of them are involved in steroid-response and oestrogen synthesis, FSH secretion, immune response, PPAR signalling pathway and the potential for DNA methylation. In conclusion, the altered transcriptomic profile of the porcine pituitary gland in pigs during the peri-implantation period indicates the role of embryos presence in the creation of transcriptomic activity of the pituitary gland in pigs.