RESUMO
Eosinophilic leucocytes, migrating in the uterine tissues during diestrus and proestrus, emigrate into the uterine cavity, being subjected to partial dystrophy. Dystrophy and assimilation of leucocytes, destroyed by the uterine tissues, especially by the endometrium, intensify and prevent emigration during proestrus and oestrus cycles. When the prior leucocyte destruction and assimilation are incomplete, phagocytosis of leucocytes and their fragments is arising, being realized by vacuolized cells of the uterine gland and epithelial lining, acquiring phagocytic properties under estrogen effect. This is the last barrier on their way to the uterine cavity, where the maximum pure genital tract flora is expedient during proestrus and oestrus. It is suggested that uterine leucocytes, representing carriers of biologically active compounds, including hormones, fulfil a transport function.