Influence of Corpus luteum Extracts upon Plain Muscle 23 



Chloroform Extract. 



The extraction with chlorofonu was made as with alcohol, bein^ 

 frecjuently repeated either with cold chloroform or with the Soxhlet 

 apparatus. The chloroform extract, after being dried and extracted with 

 Locke solution, gave in no case any action on the uterus. The residue, 

 after extraction with chloroform, dried and extracted with Locke, gave 

 in four cases a distinct increase of tone, but in one case no etl'ect was 

 produced. 



Ether Extr.vct. 



Ether extract was made in the same way as with chloroform, either 

 by repeated extraction with cold ether or by the aid of the Soxhlet 

 apparatus. Six experiments were performed with ether extract. The part 

 of the dried extract which dissolved in Locke solution produced in three 

 cases no change, in two a slight increase of tone, while in one the rhythmic 

 contractions became somewhat slower. The residue, after ether extraction 

 and drying, extracted with Locke, gave in every instance a di.stinct 

 increase of tone. 



Water Extract. 



The fresh or dried corpus luteum was either repeatedly extracted with 

 cold distilled water or a decoction was made with boiling water. The solu- 

 tions were filtered, evaporated to dryness over a water-bath, dissolved in 

 Locke solution, and this again boiled and filtered. Seven experiments were 

 performed with this w^ater extract. In all but one an increased contraction 

 was produced. In the exception, no action. The residue after extraction 

 with ether was tested in one case ; it produced no effect. The effects of 

 water extract made in the above w^ay were not so marked as those of 

 similar extracts which had been evaporated to dryness in a vacuum at 

 a temperature of 45° C. Two experiments were made with corpus 

 luteum which, after extraction with chloroform, alcohol, and ether, and 

 removal of proteins by lead acetate, was extracted with water. In both 

 of these cases the rat's uterus was caused to contract at a more rapid 

 rate and with slight increase of tone. 



Effects of the Ash. 



Dried corpus luteum was incinerated in porcelain or silicate crucibles at 

 a dull red heat. In one such estimation 3-578 per cent, ash was obtained. 

 The ash was extracted wnth cold Locke solution, boiled and filtered. The 

 eflTect of such solutions upon isolated portions of rat's uterus was usually to 

 produce inhibition : but only when the solution was strong, e.g. 5 per cent, 

 of dry corpus luteum. This inhibition is probably a potassium eff'ect, 

 since analysis of the ash, for which I am indebted to Dr W. W. Taylor 

 (see Appendix), shows a large preponderance of potassium. 



