Effects of diethylstilbestrol, 17 beta estradiol, and progesterone on plasma fibrinogen levels in rats submitted to tissue injury (laparotomy).

Participation of estrogens (17 beta estradiol, diethylstilbestrol) and progesterone in the increase of plasma fibrinogen levels in female rats submitted to tissue injury (laparotomy) was studied. Ovariectomy avoided the increase of fibrinogen observed in laparotomized rats, while the administration of 17 beta estradiol or diethylstilbestrol to laparotomized-ovariectomized rats increased fibrinogen to levels similar to those observed in the group of laparotomized rats without other treatment. On the other hand, progesterone inhibited the increase of fibrinogen which is typical of laparotomy in both groups: one of laparotomized rats and the other of laparotomized rats injected with estrogens. Neither estrogens nor progesterone modify plasma fibrinogen levels in uninjured rats. It is concluded that estrogens might participate in the fibrinogen increase observed after tissue injury in female rats, and on the contrary, the administration of progesterone would render that increase null.