ARTIFICIAL DISTENSION OF NON-PREGNANT RABBIT'S UTERUS

Manaka had been recording contractions of rabbit's uterus by making a canal on the abdominal wall. While she kept away from the experiment for several weeks the entrance of the uterus had been closed. So she opened the abdominal wall and observed the uterus, and found that the uterus was greatly enlarged like a pregnant one, assunablly due to the increase of inner pressure by stay of secreation. This induced us to the present experiment.To enlarge the non-pregnant uterus, the abdominal wall was opened and the vagina was cut off at a distance about 1.5cm from the portio uteri, and uterus canals were formed on the abdominal wall. Several laminaria halls (diameter : ca. 0.5cm) were put into the uterus on one side, then the canal was closed temporarily. Several days after, more balls (5-6) were put into the uterus, and it was removed from the rabbit on the 14-15th day of the first treatment. The uterus was greatly enlarged like a pregnant one, but the other uterus, in which no laminaria ball was put in, showed almost the same dimension as before.The histrogical examination of the tissues of the enlarged uterus showed that the muscle fibers were in somewhat stretched state, a little grown and passively extended, while in the pregnant uterus the muscle fibers were in actively extended and grown state. Except these few points, there were in actively extended and grown state. Except these few points, there was no fundamental difference beteween the tissues of uteri pregnant and artificially distended.From these results, it is assumed that the growth of the items in the prgnancy occurs merely due to the growth of the foetus, regardless of the hoi mortal conditions.