Inhibition of the receptor for tetrodotoxin in nerve membranes by reagents modifying carboxyl groups

Abstract

Tetrodotoxin binding to crab nerve fibers was measured by the bio-assay technique. Modification of fibers by a carbodiimide and nucleophile at acid ph resulted in a loss of 85% of the normal tetrodotoxin binding. Results of control experiments suggested that the inhibition of tetrodotoxin binding may be due to modification of carboxyl groups at or near the tetrodotoxin receptor.