Koziorowski, M., Krzymowski, T., Stefańczyk-Krzymowska, S., Czarnocki, J., Kotwica, J. and Zięcik, A.: Counter current transfer of polypeptide hormones from uterus to ovary in gilts using insulin as a model. Acta physiol, pol., 1988, 39 (2): 121-128. After injection of insulin or ¹²⁵I-insulin into the superficial layer of myometrium, a significantly higher level of insulin was found in blood of ovarian artery compared to systemic circulation. This result suggests that insulin chosen as a model of polypeptide hormone (mol. mass 6000 Daltons) can be counter current transferred from uterine effluent to ovary and that polypeptide hormones can be local regulatory factors in the area of the broad ligament of uterus.