Action of Shellfish Poison on Peripheral Nerve and Skeletal Muscle

Abstract

Shellfish poisoning is the paralytic type of poisoning which follows the ingestion of shellfish which have ingested the poisonous planktonic organisms. Skeletal muscles and their associated nerves in the frog, Rana pipiens. were exposed to the action of the shellfish poison. Their reaction to the poison was detd. by standard electrophysiol. techniques. It was observed that the primary action of the poison is similar to that of curare. Fistly, the poisoned muscle does not respond to stimulation via its still unpoisoned nerve and is also unreponsive to directly applied acetylcholine. Secondly, end plate potentials can be recorded and summated to produce a twitch for a period of time following the application of this material. Shellfish poison has a still more general reaction, decreasing the excitability of muscle to direct stimulation and finally also blocking nerve conduction. The action of shellfish poison was compared with that of botulinus toxin. Shellfish poison should henceforth be termed a neuromuscular toxin.