﻿THE DECREASE OF PERMEABILITY PRODUCED 

 BY ANESTHETICS 



W. J. V. OSTERHOUT 



(with six figures) 

 A number of writers hold the view that anesthetics increase per- 

 meability, while others believe that anesthetics bring about a 

 decrease of permeability. 1 It appears that the removal of this 

 uncertainty is a necessary step toward a satisfactory theory of 

 anesthesia. 



It occurred to the writer that the cause of the discrepancy 

 might lie in the fact that anesthetics produce both an increase and 

 a decrease of permeability, and that quantitative methods might 

 clear up the confusion. An investigation showed that this was the 

 case. It also demonstrated that the characteristic effect of anes- 

 thetics is a decrease in permeability. 



The investigations were begun in 191 2. A brief announcement 

 of some of the principal results has already appeared. 2 The present 

 paper gives the details of these and of later researches and contains 

 additional facts of importance. 



Since ether, chloroform, and alcohol deteriorate on standing, 

 especially when in contact with metal or with cork stoppers, special 

 care was taken to obtain pure reagents. 3 Those used were Kahl- 

 baum's or Squibb's. 



The experiments were made on tissues of the marine alga 

 Laminaria saccharina. The permeability was measured by deter- 

 mining the electrical resistance of the tissues by a method which had 

 been previously described. 4 The method may be illustrated by 

 describing a typical experiment. A lot of tissue which had a net 



' Cf. Hober, Physikalische Chemie der Zelle und der Gewebe, Vierte Auflage. 



1913; Science N.S. 37:9S9- 1913; Lepeschkin, Be^Deutsch. Bot. GeselJs. 29:349- 

 1911; Ruhland, Jahrb. Wiss. Bot. 51:376. 1912. 



