4 Kidney-Explantation and Hypertension 



actual changes that occur. Table i illustrates typical effects on the blood 

 pressure as observed in individual animals. 



On the basis of fuller data along these lines in a forthcoming paper^^ it is 

 concluded: (i) The kidneys are subject to transitory functional changes of 

 volume, which according to available evidence are most probably due to hy- 

 peremia. (2) The blood pressure of dogs also fluctuates in connection with 

 feeding. (3) Protein meals may cause no change in kidney volume, or, if the 



TABLE 1 



Examples of Dietary Influence on Blood Pressure and Kidney Dimensions. 

 Dog No. i, Normal; No. 2, with Chronic Hypertension. 



quantity of protein is sufficiently large, may cause a moderate increase, but 

 the blood pressure tends to fall. (4) Salt, water, or especially the two together, 

 regularly produce increases in both blood pressure and kidney volume. (5) 

 The changes in blood pressure and kidney volume are not strictly parallel, 

 inasmuch as: (a) they are not strictly simultaneous; (b) an increase of one may 

 accompany a decrease of the other, as mentioned under protein feeding; (r) 

 there may be discrepancies in degree; for example, with salt the increase in 

 kidney volume is similar in normal and hypertensive dogs but the rise of blood 

 pressure is slight in the former and much more marked in the latter. 



2. Acute and Chronic Hypertension 



In experiments from 1916 onward,"' it proved possible to produce diabetes 

 by brief clampings of the blood supply of a large pancreatic remnant in suc- 

 cessive laparotomies. Such experiments, applied to renal-vascular disease, have 

 a theoretical relation with the arterial spasms which are clinically familiar 

 both in local areas and in the general circulation. 



The pedicles of explanted kidneys can easily be clamped by inserting the 

 jaws of elastic intestinal forceps subcutaneously, as described by Loesch.^' In 



