198 INTERNAL SECRETIONS OF THE OVARY 



(/) THE FUNCTIONAL RELATION BETWEEN THE CORPUS 

 LUTEUM AND THE INTERSTITIAL TISSUE 



Many workers have supposed that the interstitial tissue and 

 the corpora lutea are to some extent functionaUy interchange- 

 able, and, if the former is derived exclusively from degenerate 

 membrana granulosa, the hypothesis might be supported on the 

 ground that both are of common origin. It has been shown 

 (see p. 157) that functional luteal tissue can be produced from 

 follicles without ovulation, and even from tissue which has 

 never formed part of an organized follicle; hence the normal 

 origin from an ovulated follicle is not essential. Further, luteal 

 and interstitial cells resemble each other to some extent, and 

 there are thus some histological grounds for supposing that the 

 interstitial tissue might function as a corpus luteum. 



It is necessary to consider, therefore, if there is any evidence 

 that the four functions of the corpus luteum can be carried on by 

 the interstitial tissue. As regards the inhibition of oestrus, 

 Haberlandt (256) found that the graft of a third ovary into a 

 normal rabbit caused prolonged inhibition of ovulation. Sub- 

 sequent examination of the graft showed that no corpora lutea 

 were present, but that the interstitial tissue, as is usual in such 

 grafts, was highly developed. The inhibition of ovulation was 

 ascribed to the abundance of interstitial cells. 



Pseudo-pregnant development of the uterus has also been 

 described as being initiated by interstitial tissue. Steinach and 

 Holzknecht (595) have described pregnancy changes in the uteri 

 and mammae of virgin guinea-pigs following destruction of the 

 ovarian follicles by X-rays, and they ascribe the result to the 

 action of the large amount of interstitial tissue resulting from 

 follicular degeneration. This explanation was, however, based 

 on the idea that the interstitial tissue (forming the 'puberty 

 gland') is the chief endocrine tissue of the ovary, that it 

 produces the sole ovarian hormone, and that the changes of 

 pregnancy result from increased production of the one ovarian 

 hormone. Their illustrations show a perfectly developed 

 pseudo-pregnant uterus in an irradiated animal possessing 

 no corpora lutea. 



Contrary results are found in the mouse, where X-irradiation 



