Non-Nervous Conduction in Invertebrates and Embryos

Abstract

Propagated electrical events in epithelial tissues have been recorded from a number of invertebrates and from vertebrate embryos. Those groups in which such events have been recorded are the Cnidaria, Ctenophora, Echinodermata, Urochordata, and Amphibia. In several cases these non-nervous action potentials mediate escape or protective responses. In other cases they cause ciliary reversal or arrest of ciliary beat. Propagation appears to occur via low resistance intercellular pathways involving direct current flow. The ontogeny of such epithelial impulses is described in an amphibian.