Discussion 263 



Kennedy: Dr. Fourman and I have looked at potassium-deficient 

 kidneys together many times. We agreed then that they were closely 

 similar to the kidneys we found in old rats of our own colony, and that 

 this showed that the chronic potassium-deficient kidney is simply an 

 ageing kidney. Now I am not at all sure that they are not the same thing 

 anyway: that the ageing kidney is, in a sense, a potassium-deficient 

 kidney and that there is an element of adrenal over-activity about it. 

 As you say, Dr. Milne, this may really mean that older age groups are 

 more liable to potassium-deficient states and the renal consequences of 

 that. 



Fourman : That seems to provide an explanation of why the death of 

 some nephrons appears to lead to pathological changes in the remainder. 

 From your studies. Dr. Kennedy, it seems reasonable to argue that in a 

 potassium-deficient kidney some nephrons die, and as a result in the 

 remainder there are ultimately pathological changes which are likely to 

 be worse in older rats. 



Kennedy: It is a vicious cycle and we are coming into it at different 

 points. 



McCance : Dr. Kennedy has performed a valuable synthesis in bring- 

 ing together over-nutrition, age, and lesions in the kidney. No-one asked 

 and I wish we knew what happens if these kidneys are overloaded with 

 water and with various other test substances. 



