46 WILDER TILESTON 



(4) In Obesity of Genital Origin. The obesity which often, though 

 by no means always, follows castration in both sexes, is attributed by 

 most authorities to exogenous factors, such as change of temperament, lead- 

 ing to decreased muscular activity. The altered distribution of the fat, 

 however, is sufficient justification for the assumption that an endogenous 

 factor is at work, even if it is not responsible for the generalized adiposity. 



The effect of castration on the basal metabolism has not been suffi- 

 ciently studied from the experimental point of view. Loewy and Rieh- 

 ter(a) (6), using the Zuntz-Geppert method, obtained some remarkable re- 

 sults. They found in a female dog a well-marked lowering of the basal 

 rate, beginning ten weeks after operation, and persisting throughout the 

 period of observation (six months). The reduction amounted to 20 per 

 cent of the oxygen consumption per kilo, and to 12 per cent of the total 

 oxygen consumption, although the dog gained ten per cent in weight during 

 this period, so that an increased total consumption would have been ex- 

 pected. The administration of ob'phorin (ovarian extract) caused a 

 marked rise in the basal rate, up to 38 per cent above the normal previous 

 to castration. Oophorin had no such effect on a normal bitch. 



In the case of a male dog, castration was followed by a similar but 

 lesser diminution, amounting to 13.6 per cent of the oxygen consumption 

 per kilo, the animal losing weight meanwhile. Testicular extract caused 

 a slight rise in the metabolic rate, while singular to relate, ob'phorin caused 

 an increase of 44 per cent. 



These remarkable results are much in need of confirmation. Liithje, in 

 a series of carefully conducted experiments, came to a contrary conclusion. 

 A castrated male dog and the normal control from the same litter were put 

 on the same accurately weighed diet, and confined in narrow cages to 

 restrict muscular activity. In a period of six months, each dog gained 

 in weight almost exactly the same amount. The castrate showed a rather 

 higher total daily metabolism than the control as measured in the Pet- 

 tenkofer apparatus. It should be noted, however, that the basal metabolism 

 was not determined. In a similar experiment with female dogs, the 

 spayed animal gained one kilo more than her sister before the operation, 

 and this difference was maintained afterwards. The total CO 2 excretion 

 per kilo per hour was almost identical in both animals. Loewy and Rich- 

 ter point out that the method followed by Liithje was not adapted to show 

 differences in the basal metabolism, since the gaseous exchange was meas- 

 ured over long periods, during which the taking of food and muscular 

 activity would tend to obscure differences in the basal rate, and also that 

 he failed to measure the metabolism before the operation. The whole 

 question is therefore in need of further study. 



In the case of man, there is as yet no good evidence that castration 

 lowers the basal metabolism. In Grafe's third case, a woman of 44 years 

 in whom the operation was performed for osteomalacia, and was followed 



