Discussion 197 



hormone by a change in Na/K ratios in the urine, when the change is 

 produced by two different mechanisms. 



Desaulles: I just wanted to show in this experiment that ages bring 

 changes, and sex too. 



McCance : We are deahng here with the reactions and responses of an 

 end organ, and it is a Httle difficult, apparently, to disentangle them. 



Fourman: The effects that I am speaking about concern the imme- 

 diate loss of potassium within eight hours of giving Cortisol. This im- 

 mediate large loss is completely out of proportion to any nitrogen loss, 

 and in fact precedes a measurable nitrogen loss from the body. I was not 

 concerned with the later catabolic response, only with the early potas- 

 sium loss which is quite transient, and which is what people are con- 

 cerned with when they assay so-called aldosterone activity in urine by 

 Na/K ratios. 



Milne: I am confused by your statement. Dr. Fourman. You make 

 a clear distinction between potassium excretion following (a) Cortisol, 

 and (b) aldosterone. You tell us that the potassium excretion following 

 Cortisol is out of proportion to the nitrogen loss, and therefore is a true 

 potassium excretion. You say that the difference is that potassium comes 

 from the cells, but where do you think the potassium comes from after 

 aldosterone excretion? 



Fourman : It does appear that potassium excretion after aldosterone 

 may be attributed to a change in the sodium-potassium exchange in the 

 renal tubule, whereas the large and early transient potassium excretion 

 with Cortisol is not necessarily accompanied by any retention of sodium, 

 and is associated with a rise in pH of the urine. Ultimately the potas- 

 sium has got to come from the cells in both cases. But in the first case 

 we are concerned with a primary renal effect, and in the second case I 

 suggest — and it is only a suggestion— that there may be a liberation of 

 potassium — presumably organically bound (in view of the alkaline 

 urine) — from the cells, and that may be called a primary cellular effect. 



Kennedy: Dr. Desaulles, when you spoke about the influence of sex 

 were you thinking in terms of the actions of androgens or oestrogens? 

 Your animals were not spayed, but is there a true sex difference? 



Desaulles: The effect could be changed by ablation of one of the so- 

 called specific sex organs. If you castrate males, you modify the results 

 of the experiment quite considerably; if you spay the female, the 

 changes are much less impressive, but there still remains a great 

 difference between the two sexes. I want to stress here a point that is 

 always a little puzzling to me: if you spay a female you produce a 

 marked adrenal enlargement, but if you castrate a male the enlarge- 

 ment of the adrenals is not so obvious. We do find quite a lot of sex- 

 bound differences in different functions of the animal, so I think that a 

 very important part is played by the gonads. 



Kennedy : If I understand you rightly, there is still a difference in the 

 absence of both the adrenals and the sex organs. 



Swyer : Is this difference after castration in the two sexes one which is 

 independent of the time after castration, i.e. after a long time do the 

 differences between the sexes become less? 



