QUARTERLY JOURNAL 

 OF EXPERIMENTAL PHYSIOLOGY 



THE INFLUENCE OF CORPUS LUTEUiM EXTRACTS UPON 

 PLAIN MUSCLE, ESPECIALLY THAT OF THE UTERUS. 

 By M. Itagaki. With Appendix by W. W. Taylor. (From the 

 Department of Physiology, Edinburgh University.) (With fourteen 

 figures in the text.) 



{Received for publication 2Gth July 1916.) 



That the corpus luteum is a gland of internal secretion appears to have 

 been first suggested by Prenant (1), who arrived at this conclusion from 

 the morphological character of its cells. Prenant' s conclusion has been 

 very generally accepted, and a number of suggestions have been made 

 regarding the nature of the effects which its supposed internal secretion 

 produces. The literature of the subject will be found in detail in 

 Marshall's Physiology of Reproduction; the most recent suggestions 

 are also referred to in Sir Edward Schafer's work on The Endocrine 

 Organs, pp. 145-148, and except so far as they bear upon present investi- 

 gations need not be further mentioned in this paper. 



It seems somewhat strange that, althoucrh the action of extracts from 

 various ductless glands upon the uterus, and especially that of the supra- 

 renal and pituitary body, has been investigated by several observers, very 

 few papers have dealt with the influence of extracts of corpus luteum upon 

 the contractions of the uterus, althoucrh the functions of these organs 

 are closely related. I have only been able to find references in papers 

 by Stickel (2), Fuchs (3), Guggisberg (4), and Ott and Scott (5), 

 and the results which they have arrived at have differed consider- 

 ably. Ott and Scott state that corpus luteum extract causes an increase 

 in the contractions of the uterus both in pregnant and non-pregnant 

 animals (rabbits and cats). Stickel found that in the rabbit parturition 

 was hastened by injection of corpus luteum extract. Guggisberg failed 

 to confirm Stickel's observation, and often obtained, on the other hand, 

 inhibition of uterine contractions both in pregnant and in non-pregnant 

 guinea-pigs. It seemed therefore desirable to submit the subject to renewed 

 investigation, and accordingly at the sugge.stion of Prof essor Schafer I have 

 undertaken a series of experiments with a view to determining what effect, if 

 any, is produced by extracts of corpus luteum upon the uterus ; incidentally 

 making a certain number of observations upon the action of the same 

 extracts on other muscular tissue, especially that of the intestine. 

 VOL. XL, NO. 1. — 1917. 1 



