Cholinesterase and transport of sodium chloride through gills o/Eriocheir sinensis (M.Edw.) 



Lundegardh, H. ( 1 95 1 ) . Spectroscopic evidence of the participation of the cyto- 

 chrome-cytochromeoxidase system in the active transport of salts. Ark. Kemi Min. 

 Geol. 3, 69-79. 



Massart, L. and Dufait, R. P. (1941). Hemmung der Actylcholin-Esterase durch 

 Farbstoffe und durch Eserin. Enzymologia 9, 364-368. 



Nachmansohn, D. (1950). Studies on permeability in relation to nerve function. 

 Biochem. Biophys. Acta 4, 78-95. 



Nachmansohn, D. (1952). Chemical mechanisms of nerve activity. In Modern 

 Trends in Physiology and Biochemistry. New York, Academic Press Inc. 



Quastel, J. H. and Wheatley, H. M. (1931). The action of dyestuffs on enzymes. 

 Biochem. J. 85, 629-639. 



Ramsay, J. A. (1953). Exchanges of sodium and potassium in mosquito larvae. 

 J. exp. Biol. 30, 79-89. 



Rentz, Ed. (1940). Methylenblau und Cholinesterase. Arch. exp. Path. Pharmak. 

 196, 148-160. 



Rothenberg, M. A. (1950). Studies on permeability in relation to nerve function. 

 Biochem. Biophys. Acta 4, 96-114. 



Ussing, H. H. (1948). The use of tracers in the study of active ion transport across 

 animal membranes. Cold Spr. Harb. Sym. quant. Biol. 13, 193-200. 



Ussing, H. H. and Zerahn, K. (1951). Active transport of sodium as the source of 

 electric current in the short-circuited isolated frog skin. Acta physiol. scand. 23, 

 1 10-127. 



Wigglesworth, V. (1938). The regulation of osmotic pressure and chloride concen- 

 tration in the haemolymph of mosquito larvae. J. exp. Biol. 15, 235-247. 



Wilson, I. B. (1951). Acetylcholinesterase XI. Reversibility of Tetraethyl pyro- 

 phosphate inhibition.^, biol. Chem. 190, 111-117. 



Wilson, I. B. (1952). Acetylcholinesterase XIII. Reactivation of alkyl phosphate- 

 inhibited enzyme.^, biol. Chem. 199, 1 13-120. 



Discussion 



ON PAPERS BY (i) J. F. DANIELLI AND (2) H. J. KOCH 



Chairman: J. E. Harris 



O. Maalee. Would it be possible to estimate the number of the hypothetical 'aqueous 

 pores' so accurately that it could be said whether such structures could be expected 

 to show up in electron-micrographs such as have been produced by Sjostrand and 

 his colleagues? 



J. F. Danielli. There are various methods which give a numerical value for an appar- 

 ent 'aqueous' pore, such as the kinetics of penetration or the amount of Cu+ + re- 

 quired to poison facilitated diffusion. These values agree in indicating that the 

 total area of the pores is small — probably less than I per cent, of the surface; but I 

 hesitate to place any reliance on the absolute magnitude of the figures. 



27 



