The effect of elevated potassium on the adult mollusc giant neurone survival and neurite formation in culture.

The number of viable neurones calculated as soon as adult mollusc ganglia tissue was digested and over different periods of cultivation, show that elevated K+ prevents degradation of intercellular contacts, preserves neurones against lysis, prolongs the time course of neurone survival in culture and inhibits neurite formation. K+ depolarizing effect is maintained throughout the whole course of cultivation; when elevated K+ is substituted by normal K+ the resting potential of neurones recovers. The effect of elevated K+ on neurone survival and the capability for neurite formation is not due to membrane depolarization, but seems to be related to an influence on intracellular ionic homeostasis.