CHAIRMAN'S CLOSING REMARKS 



McCance: On the opening day of this meeting Prof. Adolph dis- 

 cussed the capacity of the infant kidney to maintain the composition 

 and volume of the extracellular fluids, and he gave us a picture of its 

 responses to water, salt, and various other kinds of loading as it 

 developed. He was really discussing the ability of an " end organ " to 

 maintain the composition of the body. He said nothing about the 

 fact that the composition of the infant's body differed from that of 

 adults. We heard nothing about why such differences existed and 

 how they were maintained, yet they are the very, essence of electro- 

 lyte metabolism at that age. But the next day differences in the 

 composition of the body were considered when Dr. Olesen told us that 

 the extracellular fluids are comparatively very much larger at the 

 time of birth, and at the age of which Prof. Adolph was speaking, 

 than they are in the adult. Prof. Heller then brought up the question 

 of whether this large volume of extracellular fluid in the infant was of 

 any value or had any function. Nobody took up this challenge or 

 discussed how the volume was normally maintained. 



Prof. Kerpel-Fronius's paper, which was read by Dr. Young, intro- 

 duced some rather novel ideas which were discussed to some extent 

 but we missed the originator of them, and I would prefer to leave you 

 to make your own interpretation of them. However, I was interes- 

 ted in the point he made that the infant's water reserves and fluid 

 volumes were small relative to its normal requirements even for 

 the circulation and metabolic rate, quite apart from losses through the 

 skin. Dr. Davson brought the matter to a head, I felt, in insisting 

 that size must be clearly separated from immaturity in their effects 

 on somatic function. 



Dr. Shock showed that in advanced old age, even apart from 

 disease, the end organ begins to respond in the same kind of way that 

 it does in very early life. In both cases the end organ seems quite 

 capable of doing the work which nature intended it to do in a healthy 

 person of that age, but when one subjects it to the stresses which it is 

 capable of correcting in the young adult, one can pick out signs of 

 weakness. He did not discuss the composition and volume of the body 

 fluids in old people. Are there any steady states, normal or abnormal, 

 due to senility, either in the cell or in the body as a whole? Something 

 like this may be the basis of senility. The inability of senile kidneys 

 to maintain internal acid-base control as perfectly as those of young 

 adults was an interesting point to me. 



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