58 K. J. Franklin 



The kidney research tested the change with ageing in a 

 particular capacity of the organ, viz. its ability to reduce its 

 blood content in response to the reflex stimulus produced by a 

 given length of exposure of the whole animal to asphyxia, and 

 it showed a marked falling-off in this capacity from birth to 

 adult life. The technique used in measuring is of interest for its 

 modernity, and the findings should be of value in any final 

 explanation of the kidney's behaviour as a lender of blood to 

 other parts in response not only to asphyxia but also to many 

 other stimuli. 



The thyroid research, testing one function of the gland, 

 namely, iodine uptake, gave an answer even more emphatic 

 than the kidney research in respect of a falling-off with age. 

 The technique was again modern, making for greater speed in 

 obtaining more acceptable results. 



I think that the reactions to some other stimuli may prove 

 to be increases in functioning up to puberty, with no marked 

 changes thereafter; intra-uterine gonadotrophin effects can 

 on occasion complicate such simpler pictures. I can also 

 imagine a third class of results not to be described in terms of 

 variations in reactivity to standard stimuli, but that is going 

 outside my terms of reference. 



When a sufficient number of findings have been made about 

 ageing in studies of reactions to standard stimuli at different 

 ages, it should become possible, through this and other in- 

 formation, to produce a properly chronological account of the 

 physiology of ageing which will be a whole-life story, written in 

 an appropriate terminology and infinitely more exciting than 

 the best accounts at present available. This is in no way a 

 belittling of such accounts, but merely the credo of one person 

 in respect of the future of our as yet very young Science. 



Acknowledgement 



I wish to acknowledge the co-operation of my various colleagues 

 which has made this paper possible, the fine assistance our Departmental 

 and Animal Technicians have given us, and the liberal financial support 

 afforded by the Trustees of the Nuffield Foundation. 



