o=s8 



105' 



HANDBOOK OF PHYSIOLOGY 



CIRCULATION II 



Sawarykin ( 1 29) who noticed that ligation of a ureter 

 was followed by dilatation of the efferent renal lym- 

 phatics. Similar observations have since been made by 

 many investigators (88, 153, 154, and LeBrie and 

 Mayerson, unpublished) who have also shown that 

 renal lymph flow is significantly increased. Katz (108) 

 measured renal lymphatic pressure in two dogs with 

 pyelonephritis and found the pressures to rise when 

 either the renal vein or the ureters were compressed. 

 It is apparent that the renal parenchyma shows no 

 significant changes for a number of weeks after the 

 experimental ligation of the ureter; the only histo- 

 pathological symptoms that can be observed for a 

 considerable time are a high degree of interstitial 

 edema and marked dilatation of lymphatics. Babies & 

 Rrnyi-Yamos (7) ascribe the survival and continued 

 performance of the hydronephrotic kidney to the fact 

 that urine passes from the renal pelvis into the inter- 

 stitial space of the kidney where it is continuously 

 absorbed into lymphatics. Histamine is presumed to 

 be liberated, increasing capillary permeability and 

 transudation of protein. This protein, too, is carried 

 away by the lymphatics. If, on the other hand, the 

 lymphatics are also tied off, necrosis is seen within a 

 few days [see Babies & Renyi-Vamos (7) andRusznyak 

 el al. (189) for detailed discussion]. 



The general effect of diuretics is to increase renal 

 lymph flow. Reference has been made to the work of 

 Schmidt and Hayman who showed this to be true for 

 phosphate, sodium chloride, and caffeine. We have 

 collected renal capsular lymph in dogs during diuresis 

 produced by sodium chloride, urea, mannitol, and 

 mercury (LeBrie and Mayerson, unpublished). Under 

 the conditions of our experiments, we obtained the 

 most marked diuresis with urea and mannitol and the 

 least with mercury. Mannitol produced the greatest 

 increase in lymph flow (average 10 dogs = 587%), 

 while mercury and urea produced the least (Hg, 15 

 dogs, 42 %; urea, 7 dogs, 41 '", ). These experiments are 

 being continued and attempts are being made to eluci- 

 date the mechanism of the changes in flow, electro- 

 lyte and protein concentration, and to explain the 

 differences seen with the different diuretics. 



We have also studied the influence of uranium- 

 nitrate injury on the flow and composition of renal 

 lymph (122). Lymph flow was increased approxi- 

 mately 15 times in the experimental animals. Like- 

 wise, the increase in lymph flow with mannitol 

 infusion was about twice as great in the experimental 

 animals (iooo f T increase) as in control animals 

 (542% increase). The experimental animals showed 

 a significant proteinuria and decreased urine flows, 



and the data appear to be consistent with the histo- 

 logic findings of primary damage to the distal seg- 

 ment of the proximal tubule. 



The finding of an increased lymph flow when 

 ureters are obstructed and diuretics are administered 

 has given rise to the concept emphasized in clinical 

 literature, that the renal lymphatics act as a "safety- 

 valve" mechanism, capable of taking the extra load 

 from the kidney under conditions of overload. 

 Backflow from the kidney pelvis to the renal lym- 

 phatics has also been suggested by experiments of 

 Murphy & Myint (153) and Goodwin & Kaufman 

 (89). The former introduced glucose and the dye 

 T-1824 into the renal pelvis and found these sub- 

 stances earlier and in greater concentration in lymph 

 of the cisterna chyli than in renal or femoral blood. 

 The latter injected radioactive Diodrast into the 

 renal pelvis during ureteral occlusion and found 

 the same radioactivity at the same time in thoracic 

 duct lymph and in the control vascular area. More 

 work along these lines is needed, particularly defining 

 the mechanisms involved and the effects of pyelo- 

 lymphatic backflow in kidney disease. However, it 

 may be pertinent to emphasize, as has been previously 

 suggested, that the general function of the lymphatic 

 system is to act as a "safety valve" and as an acces- 

 sory circulation, clearing the interstitium of excess 

 substances which leak out of or are not absorbed 

 directly into the blood stream and returning them to 

 the blood circulation. This is not a peculiar or special 

 function of renal lymphatics. Thus, an overload of 

 the circulatory capacity as produced by a large 

 intravenous infusion results in an increased lymph 

 flow, etc. The particular importance of lymph with 

 respect to normal renal function lies in the fact that 

 the oncotic pressure of the interstitium must be kept 

 low in order for the vasa recta to act as a counter- 

 current exchanger. In the absence of adequate 

 lymph drainage the kidney becomes unable to 

 concentrate urine (105). 



LYMPH AND LYMPHATICS IN SHOCK 



Anaphylactic Shock 



Petersen & Levinson (173) found that injection of 

 antigen into dogs resulted in an increased perme- 

 ability of splanchnic endothelium and subsequent 

 reaction of the hepatic parenchymal cells with the 

 antigen. In further work, Petersen & Hughes (172) 

 showed the injection of egg white into dogs sensitized 



