[Intracellular local changes of resistance in muscle fibers in relation to membrane potential]

Intracellular local changes of resistance in sartorius muscle of the frog were investigated. The changes of resistance that were earlier shown to be located very near to the tip of the microelectrode appear in response to the changes of membrane potential evoked in various ways: polarization with electric current, depolarization with increase of the extracellular [K+], generation of action potentials. Depolarization leads to the local decrease of resistance, hyperpolarization--to increase of it. By using the tree-barreled microelectrodes with various geometry of the cross section, an attempt was undertaken to check some spatial peculiarities of the structure responsible for the local changes of resistance.