Decreased fibrinolytic activity in the rat uterus after laparotomy.

The influence of different intrauterine devices (IUDs) on the uterine fibrinolysis has been extensively studied in rodents with two uterine horns. In this experimental model an IUD is inserted into one horn by a surgical procedure including laparotomy and uterotomy. The effect of these two surgical steps on the fibrinolysis in the endometrium determined according to Todd's histochemical fibrin slide technique was studied in the present series comprising 26 rats. The fibrinolytic activity (FA) in the rat uterus was independent of the biopsy site in the uterine horns. However, significant depression of endometrial fibrinolysis was demonstrated 2 weeks after laparotomy, whereas no effect of a tiny incision in the uterine wall was recorded. In conclusion, a sham operation of the control horn in rodent studies on the fibrinolytic effect of IUDs according to this experimental model is not necessary.