ESTROGEN AND PROGESTERONE 



563 



Figs. 9.5 and 9.6 



The uteri of these two castrated monkeys were opened from fundus to cer\'ix by an incision 

 through the anterior wall while the animals were receiving estrogen. Part of the endometrium 

 of the anterior wall was removed and the incision in the myometrium was not closed. 



Fig. 9.5. Estradiol, 10 fig., was given daily for 7 days; the uterus was opened and the animal 

 continued on 30 /xg. estradiol daily for 40 days. (From F. L. Hisaw, in A Sy7nposiii7n on Steroid 

 Hormones, University of Wisconsin Press, 1950.) 



Fig. 9.6. Estradiol, 10 ^g., was given daily for 7 days; the uterus was opened and the treat- 

 ment continued at a dosage of 30 /ig. estradiol daily for 20 days. (From F. L. Hisaw, in A 

 Symposium on Steroid Hormones, University of Wisconsin Press, 1950.) 



serving changes in the endometrium (luring 

 the normal menstrual cycle. This procedure 

 makes frequent inspections possible either 

 by hand lens or dissecting microscope, of 

 most of the upper part of the endometrium 

 on the anterior and posterior walls of the 

 uterus. The elliptic slit formed by the endo- 

 metrium of the two opposing walls can be 

 located easily, the two sides pressed apart 

 by any small smooth instrument, and the 

 surface of the endometrium examined. 

 Changes in thickness of the endometrium 

 cannot be ascertained without resorting to 

 biopsies but it is free to grow out of the 

 opened uterus if it is so inclined. However, 

 in such preparations the growth produced in 

 the endometrium by daily injections of 10 

 fjig. estradiol for periods of 2 or 3 weeks is 

 not sufficient to show any tendency what- 

 ever to grow out through the fistular open- 

 ing or obstruct examination of the walls of 

 the uterus. The limited growth observed in 

 these experiments is in agreement with that 

 obtained with estrogen on intact and incised 

 uteri. 



The cervix uteri of the rhesus monkey is 

 sufficiently long to make it possible to bring 

 the entire fundus to the exterior through a 

 midal)dominal incision. Advantage of this 



was taken in an attempt to exteriorize the 

 uterus and maintain it outside the body for 

 long enough periods to make it possible to 

 study the growth responses of the endome- 

 trium (Hisaw, 1950). These preparations 

 did not i)rove satisfactory in all respects but 

 they did contribute a number of interesting 

 observations. 



The operational i^rocedure used in these 

 experiments involved dividing the uterus 

 transversely from fundus to cervix so that 

 the anterior wall was deflected downward 

 and the posterior wall upward (Fig. 9.7). 

 The endometrium of the exteriorized uterus 

 is difficult to maintain but with proper care 

 it seems to retain its normal condition for 

 at least the first few days after the uterus 

 is opened. Small localized areas of ischemia 

 can be seen to come and go, probably action 

 of the coiled arteries, and there is a periodic 

 general blanching of the endometrium as- 

 sociated with rhythmic contractions of the 

 muscularis. This, however, does not seem 

 true of the whole endometrium. A zone sur- 

 rounding the internal os of the cervix tends 

 to retain its blood-red color even during 

 strong contractions of the uterus and the 

 growth reactions of the endometrium in this 

 area are of particular interest. 



