ANTAGONISM BETWEEN SALTS AND ANESTHETICS 603 



hypertonic sea-water exerts its characteristic action primarily 

 by changing the state of the plasma-membrane, and that the 

 oxidative processes underlying the favorable effect of this after- 

 treatment are a function of certain membrane-processes. We 

 have thus further though somewhat indirect evidence that the 

 plasma-membrane is a controlling factor in the intracellular 

 oxidations. !■* 



Chloral hydrate has little effect in preventing the action of 

 0.55 m KCNS. In five experiments with this anesthetic, in 

 concentrations of 0.2 per cent to 0.1 per cent, the highest pro- 

 portion of eggs remaining unaltered next day was ca. 10 per 

 cent (table 5). Potassium cyanide showed no signs of protective 

 action in any experiment. The series shown in table 3 illustrates 

 the results obtained with these compounds. 



It will be noted that although chloral hydrate and cyanide are 

 almost without influence on the cleavage-initiating action of 

 0.55 m KCNS, both prevent entirely the favorable effects of after- 

 treatment with hypertonic sea-water. This action was highly 

 striking in the above series, since in every experiment the great 

 majority of eggs formed blastulae after treatment with the pure 

 hypertonic sea-water. 



Experiments with sodium iodide 



In experiments with this salt all the above alcohols showed 

 well-marked protective action. The series summarized in table 

 4 will illustrate. The eggs were exposed to the freshly prepared 

 0.55 m Nal for four minutes; this is too brief an exposure to cause 

 membrane-formation in all eggs, and about 20 per cent remained 

 intact next morning; the proportion remaining intact was, how- 

 ever, much greater in the anesthetized lot, and fewer of these 

 eggs formed blastulae. 



A second similar series with five minutes' exposure to 0.55 m 

 Nal, and containing in addition to the above alcohols ethyl 

 urethane and chloral hydrate, gave similar results, although the 

 protective effect was on the whole less pronounced. Urethane 



^^ For more direct evidence of a relation of membranes to oxidations, cf . my 

 recent paper in the Journal of Biological Chemistry, 1913, vol. 15, p. 237. 



THE JOURXAT, OF EXPERIMENTAL ZOOLOGY, VOL. 16, NO. 4 « 



