Tissue Culture of Squid Neurons, Glia, and Muscle Cells

Abstract

We first became interested in the culture of squid neurons as an adjunct to our studies of membrane channels in excitable membranes and our investigation of axoplasmic transport in squid giant axons. For several decades the squid giant axon was the quintessential preparation for the study of the properties of sodium and potassium channels in excitable membranes (Hodgkin, 1951; Cole, 1968; Adelman, 1971; Armstrong, 1975; Adelman and French, 1976). With the advent of single channel recording (Bean et al., 1969; Ehrenstein, Lecar and Nossal, 1970) in lipid bilayers and with the patch clamp technique being applied to living membranes (Neher and Sakmann, 1976), it soon became possible to relate the ensemble properties of excitable membranes to the summation of unitary events occurring in single channels in bilayers (Ehrenstein, Lecar, and Nossal, 1970; Ehrenstein et al., 1974) and in living cell membranes (Sigworth and Neher, 1980). Our desire was to obtain clean cultured squid neurons free of glial cells so that we could easily patch clamp single sodium or potassium channels in the membranes of these cultured cells and then predict and verify the ensemble properties of the excitation process from the single channel patch clamp data. The vast archive of information already in existence as to the electrical behavior of the squid giant axon made this cell culture effort seem particularly tantalizing.