Distribution of Cyanole and Neutral Red in the Giant Axon of the Squid

Abstract

PREVIOUS work on the permeability of frog muscles¹ and giant axons of Cephalopoda^2,3 to vital dyes has shown that basic and acid dyes rapidly penetrate the cell and its intracellular content may be less or greater than in the medium, depending on the outside concentration and type of the dye. For giant axons in the steady state the coefficient of distribution (Q = C_in/C_out, where C_in and C_out represent respectively intra- and extra-cellular concentration) for the acid dye (cyanole) was found to be 0.12 with the external dye concentration varying from 0.1 to 1.0 per cent (ref. 3). At the same time the coefficient of distribution of the basic dye (neutral red) changed from 5.5 to 0.65 on a corresponding increase in C_out from 0.004 to 0.16 per cent (ref. 2).