Effect of uterine artery ligation on ovulation in the rat

Female rats were divided into six groups: (1) control, (2) one uterine artery (a.) ligated near the utero-tubal (U-T) junction, (3) one uterine a. ligated at the level of the cervix, (4) both uterine aa. ligated separately at the U-T junction, (5) both uterine aa. ligated separately at the cervix and (6) both uterine aa. tied with one ligature at the cervix. Segmental aa. were disrupted in all experimental groups except group 6. Animals were allowed to recover for ten days and killed the first metestrus thereafter. Number of eggs ovulated was determined by flushing the oviduct with saline solution and counting the ova. Control rats ovulated 5.0 +/- 0.4 eggs per ovary. Groups 2 and 3 had an increase in the number of eggs shed from the ovary on the non-ligated side. In contrast, a decrease in the number of ova shed occurred on the ligated side. When both aa. were ligated separately (groups 4 and 5), irrespective of location, a decrease in the number of eggs shed by both ovaries was evident. No effect was found when only one ligature was placed near the cervix (group 6). The data demonstrate that blood supply to the ovary via the uterine artery is essential for the full complement of eggs to be shed.