The voltage-clamp method

The paper presents the voltage-clamp
 method used for measuring electrical current
 passing the cell membrane and for calculating 
its conductance. The basic principles of this 
technique are described, as well as the apparatus used for the measurements in giant axon 
of the squid and the end plate region of the 
muscle fibre. A diagram presenting a negative
 feed-back is included as an illustration of the
method. In the Appendix, some measurements
 simulated by using the Microcap computer programme are presented.