Permeability of the Capillary Walls. 201 



107 (1567) 



The effect of solutions of certain salts and colloids on the permea- 

 bility of the capillary walls. 



By Arthur H. Smith and Lafayette B. Mendel. 



[From the Sheffield Laboratory of Physiological Chemistry, Yale 

 University, New Haven, Conn.] 



In order to study the permeability of the capillary walls for 

 various substances, the material was injected, in isotonic solution, 

 intravenously into rabbits, the diffusion out of the circulation 

 being estimated by the relative concentration of the blood as 

 indicated by the hemoglobin. The rate of injection was such that 

 a volume of fluid equal to the estimated blood volume was intro- 

 duced in two minutes. 



When the chloride, bromide, sulfocyanate, nitrate or acetate 

 of sodium was used, the blood volume returned to normal in 

 thirty minutes. When the tartrate, citrate or sulfate was used 

 the blood volume remained somewhat higher than normal through - 

 the experiment which usually lasted more than two hours. 



The injection of M/15 hydrochloric acid, calcium chloride or 

 colloidal silver (Solargentum, Squibb) produced no delay in the 

 removal of fluid from the circulation. Acacia, however, markedly 

 sustained the increased blood volume at a point one third above 

 the normal for more than two hours. 



Under the conditions of these experiments, there was no evi- 

 dence of edema or of increased water content of the muscles even 

 after repeated injections. The excess of fluid was eliminated 

 through the gastro-intestinal tract, the kidneys and to a slight 

 extent, into the serous cavities. 



