THE TESTICLE AND THE OVARY 329 



Zoth, 1 and also Pregel, 2 state that they have obtained evidence by 

 ergographic records of the stimulating action of testicular extracts 

 upon the neuro-muscular apparatus in the human subject. They are 

 of opinion that the injection of such extracts results in a decrease of 

 nervous and muscular fatigue, and at the same time diminishes the 

 subjective fatigue sensations. 



The composition and physiological properties of testicular extract 

 have also been investigated by Dixon, 3 who found it to contain 

 proteins, organic substances unaltered by boiling, and inorganic salts. 

 Nucleoprotein was especially plentiful. Injection into the circulation 

 caused a fall of blood pressure due chiefly to cardiac inhibition, but 

 no very striking or interesting results. 



Walker 4 appears to be dubious about the efficacy of testicular 

 medication, stating that the injection of fluid extract into castrated 

 dogs had no effect in arresting the atrophy of the prostate gland 

 (of. de Bonis, see Chapter VII., p. 251). It is possible, however, 

 that the " active principle " of the testicular secretion was destroyed 

 in the preparation of the extract, and that the constant administra- 

 tion of fresh testicular substance might have led to a different result. 

 In these experiments extract of the whole gland seems to have been 

 used and not of the interstitial gland only. 



Bourn and Ancel 5 showed in the horse and other animals that 

 when the vasa deferentia are ligatured the spermatogenetic tissue of 

 the testis ceases to be functional and gradually undergoes degeneration, 

 while the interstitial cells remain unaffected. They pointed out, 

 further, that those cells have a distinctly glandular appearance, and 

 that their presence suffices for the development of the secondary sexual 

 characters. Consequently they drew the conclusion that the testis 

 is an organ producing an internal secretion which is elaborated by 

 the interstitial cells and not by the spermatogenic tissue. Copeman," 



1 Zoth, "Zwei ergographische Versuchsreihen tiber die Wirkung orchitischen 

 Extractes," Pfliiger's Arch., vol. Ixii., 1896. 



2 Pregel, "Zwei weitere ergographische Versuchsreihen, etc.," Pfiiigei's 

 Arch., vol. Ixii., 1896. 



3 Dixon, " A Note on the Action of Poehl's Spermine," Jour, of Physiol., 

 vol. xxv., 1900; "The Composition and Action of Orchitic Extracts," Jour, of 

 Physiol,, vol. xxvi., 1901. According to Hervieux, the interstitial gland of the 

 testis contains a ferment which splits neutral fats, and converts dextrin, maltose, 

 and glycogen into glucose but has no action on lactose (C. R. de la 3oc. Biol., 

 vol. lx., 1906). 



4 Walker (G.), "Experimental Injection of Testicular Fluid, etc.," Johns 

 Hopkins Hospital Bidletin, vol. xi., 1900. 



6 Bouin and Ancel, " Recherches sur les Cellules interstitielles du Testicule 

 des Mammiferes," Arch, de Zool. Exper., vol. i., 4th series, 1903. 



Copeman's experiments, which were upon the rabbit, were not published, 

 but were personally communicated to Swale Vincent, and alluded to by him in 

 a lecture on " Internal Secretion and the Ductless Glands," Lancet, 1st August 

 1906. See also Copeman, "Experiments on Sex Determination," Proc. Zool, 

 Soc., 1919. 



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