embryokine embryokine embryokines (greek: embryuon "embryo" + kinōs "movement") are regulatory molecules produced by the oviduct and endometrium in the reproductive tract that modulate embryonic growth and development. embryokines include growth factors such as insulin-like growth factor-1, and activin a transforming growth factor; cytokines such as colony stimulating factor 2, wnt regulatory proteins including dkk1; other small molecule amino acids are included that regulate embryonic development through the mtor signalling pathway. prostacyclin 1 can activate peroxisome proliferator-activated receptor 6 to increase blastocyst hatching, and cannabinoids that can also act to regulate implantation and development.