212 



PRINCIPLES OF GENERAL PHYSIOLOd'Y 



Antagonism of Salts. In these physiological saline solutions we see how one 

 salt alone is unable to preserve the excitability of living tissues, and we are 

 reminded of the similar phenomena in the effect of salts on the permeability of the 

 cell membrane. In this latter case we found that, as a rule, the action of a single 



1. 



Fin. 65. EFFECT OF LIPOID CONSTITUENTS OF SERUM ON HYPODYN\MI< MKART. 



1. Beats of heart rendered hypo<h nainic by prolonged ]>erfiisioi] with Ringer's solution. 



At A the constituents of serum which are insoluble in alcohol were added ; there is no effect. 



Tin- jmlse volume (P.v.) increases merely from 0-026 to 0"033 c.c. 

 I. At B marked effect of the alcohol-soluble constituents of serum. I'ulxe volume increased in 



60" from 0"02 c.c. to 0'12 c.c. 



:5. Effect of ether extract of dry residue of alcoholic extract of serum, introduced at A. 

 4. Similar effect of sodium soap of the above ether extract. 



(Clark, 1913, 2, p. 94.) 



salt is to cause a loss of the semi-permeable properties of the membrane, and it may 

 well be that we have to do with related phenomena in the behaviour of cells to 

 perfusion fluids. 



The way in which one salt is able to neutralise the toxic properties of another 

 is, as yet, by no means clear. Loeb (1903) showed that a marine Gammarus dies 

 in half an hour if transferred to cane sugar or pure sodium chloride isotonic with 



