348 RALPH S. LILLIE. 



tissue-extracts indicate that the normal oxidations in living cells 

 like muscle-cells are far more rapid and complete than can be 

 effected through the simple agency of the oxidases present 

 (Fletcher and Hopkins, Warburg, Battelli and Stern) 1 ; the role 

 of oxidases in cell-respiration may therefore well be a subsidiary 

 one; and if so, the fact that anaesthetics arrest cell-activities in 

 concentrations which are without direct influence on the oxidases 

 may be understood. The essential change in anaesthesia would 

 then be a reversible alteration of certain structural elements that 

 control oxidations as well as other cell-processes. 



Such a view would regard oxidases as accessory rather than 

 primary factors in cell-oxidations. If this is true, there should 

 be no direct parallelism between decrease of oxidations and 

 anaesthesia; and it should be possible in certain cases to secure 

 anaesthesia without influencing oxidations. There are in fact 

 numerous instances of complete and typical anaesthesia unaccom- 

 panied by any essential decrease in the rate of oxidations. 

 The anaesthesia of anaerobic animals and yeast-cells has already 

 been cited ; these instances, however, may be considered equivo- 

 cal, since oxidations are equally essential to metabolism in 

 these organisms even though molecular oxygen may not take part 

 in the reactions. But many cases are known where the activity 

 of aerobic organisms or tissues may be profoundly inhibited by 

 anaesthetics, while the rate of oxidation is unaltered or only 

 slightly decreased. Such lack of parallelism was observed by 

 Rhode and Ogawa for the influence of chloral hydrate on the 

 isolated heart. 2 The case of cell-division in developing eggs is 

 an especially clear one; here the rate of oxidation is relatively 

 slight compared with that of active muscle-cells. Warburg found 

 that phenyl urethane in concentrations of m/2,ooo arrests cell- 

 division completely in sea-urchin eggs (Strongylocentrotus) , while 

 leaving oxygen-consumption essentially unchanged ; in order mate- 

 rially to decrease oxidations (by 40 per cent.) several times the 

 minimal anaesthetic concentration was needed (m/'^oo). 3 Similar 



1 Fletcher and Hopkins, Journ. Physiol., 1907, Vol. 35, p. 287; Warburg, 

 Zeitschr. f. physiol. Chem., 1911, Vol. 70, p. 413; Pfluger's Archiv, 1912, Vol. 145, 

 p. 277; Battelli and Stern, Biochem. Zeitschr., 1914, Vol. 67, p. 443. 



" Rhode and Ogawa, Archiv /. exper. Path. u. Pharm., 1912, Vol. 69, p. 200. 



'" Warburg, Zeitschr. f. physiol. Chem., 1910, Vol. 66, p. 305; 1911, Vol. 70, p. 413. 



