Generation of calcium action potentials in crustacean muscle fibers following exposure to sulfhydryl reagents

Abstract

1. The ventroabdominal flexor muscles of the crustacean Atya lanipes, which are normally completely inexcitable, generate trains of overshooting calcium action potentials after exposure to the sulfhydryl reagents known as α,β -unsaturated carbonyl compounds. 2. The chemically induced action potentials are abolished by protein reagents specific for guanidino and amino groups. 3. Attempts to induce excitability by the use of agents that block potassium conductance were without success. 4. It is proposed that calcium channels are made functional by the covalent modification of a calcium protochannel, via the interaction between the introduced carbonyl group and existing arginine residues.