EFFECTS OF EXTRACTS OF THE UTERUS 101 



and guinea-pigs certain epithelioid cells (? decidual cells), The uterus 



' and internal 



which are formed during pregnancy, and which consti- secretion. 

 tute what these writers term the 'myometrial gland', 

 give rise to an internal secretion which is specially con- 

 cerned with the secretion of milk. 



PHYSIOLOGICAL EFFECTS OF EXTRACTS OF THE UTERUS 



In 1909 Hick and I recorded 1 experiments in regard Effects of 

 to the effects produced by injections of uterine secretion the^terus. 

 which was obtained by ligation of the uterine horns in 

 rabbits. We observed distinct pressor effects, especially 

 in regard to uterine contractions. Fellner 2 subsequently 

 noticed a vasoconstrictor effect following intravenous 

 injections of an extract of the uterus. Mackenzie 3 has 

 found that extracts of the uterus involuting after par- 

 turition cause an increase in the flow of milk from the 

 incised nipples of lactating animals. 



In spite of my original suggestions, and in spite of the 

 statements presented above, I am now of the opinion 

 that there is insufficient evidence to prove that the 

 endometrium itself forms an internal secretion. 



Because the endometrium is able to cause the uterus not 

 disappearance of fibrinogen and fibrin ferment fromj^^J 10 

 menstrual blood, and so prevent coagulation 4 , and secretion. 

 because the external secretion and extracts, as already 

 mentioned, have physiological pressor properties, it by 

 no means follows that there is also an internal secretion. 

 Even the presence of tryptic ferments 5 ' 6 , is no evidence 

 of a cryptorrhreic function. There may, possibly, be 



1 Bell, W. Blair, and P. Hick, Brit. Med. Journ. , 1909, vol. i,p. 777. 



2 Fellner, O. O., Centralblf. Physiol, 1909, vol. xxiii, p. 347. 



3 Mackenzie, K., Quart. Journ. Exper. Physiol., 1911, vol. iv, p. 305. 



4 Bell, W. Blair, Proc. Roy. Soc. Med., 1911, vol. iv, p. 234 ; Journ. 

 Pathol. and Bacteriol., 1914, vol. xviii, p. 461. 



5 Halban, F., and 0. Frankl., Gynak. Rundschau, 1910, vol. iv, 

 p. 471. 



6 Frankl, O. and B. Aschner, Gynak. Rundschau, 1911, vol. v, 

 p. 647. 



