178 



JiRi K^ECEK, et al. 



pituitary mechanisms regulating the metaboHsm of water and 

 electrolytes. At the end of the fourth week of life the effect 



Renal 

 water 

 loss 



Renal 



sodium 



loss 



23 days 

 ml/lOO g 



33 days 



Renal 



potassium 



loss 



^q/100 g 

 -450 



-300 



[-150 







r^^^M 



czi 



controls 



cortisone 



ACTH 



ACTH •» cortisone 



Fig. 7. The effect of cortisone and ACTH (for doses and duration of adminis- 

 tration see Fig. 5) on renal losses of water, sodium and potassium during the 

 first three hours after administration of a water load (4-5 ml./lOO g. body wt.) 

 to young rats aged 23 and 33 days. 



of vasopressin on elimination of a water load changes. This 

 is in agreement with Heller (1952). In addition, at this time 

 vasopressin begins to have an effect on sodium elimination. 



