226 Freeman, Pincus, Elmadjian and Romanoff 



which is greater in the normal group than in the patients, 

 but not to a statistically significant degree. In younger 

 individuals the normal subjects show a significantly greater 

 response (Hoagland et al., 1953). 



The greater reactivity noted in the response of the normal 

 subjects is not due to any influence of the initial level. No 

 relationship can be demonstrated between the control levels 

 and the magnitude of the change at the four-hour reading. 



The sodium/creatinine excretion data in Table III show 

 identical basal values for the two groups of subjects. In 

 younger subjects, patients usually excrete more sodium 

 (Pincus et al, 1949). Their response to the injection of ACTH 

 is distinctly different. The normal subjects show a steady 

 rise, more marked in the first two hours, the final level 

 reached being an increase of 65 per cent. In the case of the 

 patients, there is an insignificant rise at the two-hour reading 

 and then a decrease in excretion to a point slightly below the 

 initial leveJ. At both the two- and four-hour points, the 

 response of the normal subjects is statistically significantly 

 greater than that of the patients. A similar lesser responsivity 

 is characteristic of young schizophrenic patients also. 



Again, the responsivity of sodium to ACTH is independent 

 of the initial level and, since both groups have the same mean 

 basal values, the difference in trends is therefore more striking. 



Turning next to the data on potassium-creatinine ratios 

 (Table III), we see that in the basal levels the patients 

 excrete a lesser amount than the normal subjects. The 

 reverse is true in younger subjects (Hoagland et al., 1953). 

 After the administration of ACTH, the excretion is increased 

 in both groups, but significantly more in the normal subjects. 

 In this respect again, the greater response of the elderly 

 normal subjects as compared with the patients is a reflection 

 of what has been noted in younger subjects (Pincus et al., 

 1949). The initial level plays no role in the greater responsivity 

 of the normal subjects, there being no relationship between 

 the control values and the amount of change at the four-hour 

 point. 



