EN
Krzymowski, T., Stefańczyk-Krzymowska, S. and Koziorowski, M.: Counter current transfer of PGF₂ α in the mesometrial vessels as a mechanism for tprevention of luteal regression in early pregnancy. Acta physiol, pol., 1989, 40 (1): 23-34. A new concept has been presented on the mechanism protecting the corpus luteum during oestrouis cycle, early pregnancy and pseudopregnancy induced by oestrogens. The concept is based on the recently discovered mechanism of (back transfer of prostaglandin F₂ α from the broad ligament vasculature into the uterus and on the participation of oestrogen in this process. The morphological facilitates for counter-current transfer of PGF₂α in the area of mesometrial vasculature and ability the uterus to bind PGF₂α were presented. It has been concluded that the process of PGF₂α back-transfer from mesometrial vasculature into the uterus may reduce in uterine venous blood the amplitude of PGF₂α pulses and by his way may reduce the penetration of prostaglandin into subovarian area and from there to the corpus luteum.