136 The Endocrine Organs 



degeneration, although the interstitial tissue is not, at first at any rate, 

 attacked. Young animals so treated develop normal secondary sexual char- 

 acters. Moreover, remarkable cases have been described, in both the male 

 and female sex, in which tumours of the testicle and ovary, apparently 

 malignant in character, occurring in children, have been accompanied by a 

 general growth of stature and by premature appearance of secondary sexual 

 characters, such as growth of hair on the face in the male and in the arm- 

 pits and on the pubes in both sexes, development of breasts and external 

 generative organs : in short, all the signs of puberty ; which, on removal 

 of the tumour, have been found to disappear. These seem to be cases of 

 tumour cells taking on the functions of normal cells (in this case interstitial 

 cells) from which they have developed (see p. 33). 



EFFECTS OF EXTRACTS OF TESTICLE 



Brown-Sequard was of opinion that subcutaneous injection of testicular extracts 

 has the effect of producing a bodily and even more a mental rejuvenation, and he 

 ascribed this to the occurrence in such extracts of certain principles which are 

 taken up into the blood, and through this act upon the nervous system. He 

 supposed that similar principles are produced also in the ovaries, but to a less 

 extent. The results he announced ikave not, however, been obtained by others 

 who have tested the physiological effects of such extracts, and the views he enunci- 

 ated have not obtained general assent, although certain observers claim to have 

 obtained positive effects on the growth and development of young castrated animals, 

 and also of immature entire animals. 



Intravenous injections of testicular extracts produce no immediate results 

 except a fall of blood-pressure, due, according to Dixon, to cardiac inhibition. 



