Electrotonic coupling in internally perfused crayfish segmented axons.

Abstract

A technique was developed for cannulation and internal perfusion of crayfish segmented lateral axons. Experiments on perfused and non-perfused axons showed that internally perfused segmented axons behave very similarly to non-perfused axons. The axial electrical resistance of the junctional region is almost as low as a comparable segment of axon. Neither intracellular Ca2+ nor H+ is effective in disrupting the intercellular communication pathway in perfused axons. On the basis of these findings a hypothesis was formulated for cellular control of intercellular coupling based on the existence of a soluble intermediate for Ca2+ or H+-induced uncoupling. This hypothesis is consistent with data from both internally perfused and non-perfused axons.