Selection of variant neuroblastoma clones with missing or altered sodium channels.

Abstract

Neurotoxins that cause persistent activation of voltage-sensitive Na channels are highly cytotoxic to electrically excitable neuroblastoma cells. These toxins were used as selective agents to isolate variant [mouse] neuroblastoma clones with missing or altered Na channels. Of 10 resistant clones analyzed, 7 lacked functional Na channels and 1 had a specific 40-fold increase in Kd for scorpion [Leiurus quinquestriatus] toxin and altered voltage dependence of scorpion toxin binding. The phenotypes of these cell clones were stable for more than 100 generations, indicating that they were the result of stable genetic change.