THE CORPUS LUTEUM, ITS STRUCTURE 



AND FUNCTION 



By CHAS. H. O'DONOGHUE, D.Sc. 



Beit Memorial Felloiv, Zoological Laboratory , University College, London 



Introduction 



Long ago it was known that in the mammalian ovary sometimes 

 a well-marked bright yellow body, the corpus luteum, appeared, 

 easily recognisable with the naked eye ; and its nature and 

 function were the subjects of much speculation. In recent years 

 a great deal of attention has been paid to this structure, and 

 some light has been thrown on its histology and function. It 

 is hoped it will be of interest therefore to set out the facts and 

 theories recently brought forward regarding this body, which 

 we now recognise as a ductless gland, and the part it plays in 

 the chemical co-ordination of the body. 



It is now generally known that in the female mammal the 

 ovary is in a state of activity during the years intervening 

 between puberty and senescence. This activity varies in 

 intensity, and becomes very strongly marked at recurring 

 intervals. The time elapsing between two periods of maximum 

 activity varies from about a year {e.g. Monotremes, Mar- 

 supials (9), etc.) to about a month {e.g. Primates, etc.). The 

 ovarian changes are frequently accompanied by well-marked 

 alterations in the external appearance or behaviour of the 

 animal, and these latter have long been recognised by the 

 breeder under the name of "heat" or "rut." The climax of 

 the period of ovarian activity is, in general, marked by the 

 liberation of a ripe ovum or ova, and this is immediately 

 followed by the formation of corpora lutea. 



Before passing on to consider the corpus luteum itself it is 

 necessary to glance, albeit quite briefly, at the structures present 

 in the ovary prior to the setting free of the eggs. 



The mammalian ovary consists of a mass of connective 

 tissue, the stroma, which contains some plain muscular fibres 



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