Selective Block of Synaptic Transmission in Ciliary Ganglion by Type A Botulinus Toxin in Rabbits

Abstract

By following a retrobulbar injection of type A botulinus toxin in 15 minutes with parenterally administered type A botulinus antitoxin, there develops a dilated pupil (fixed to light) on the injected side in the majority of surviving animals. Electrical and pharmacological data indicate a block of the level of the synapse in the ciliary ganglion. The fixed pupil persists for at least 6 months as an isolated finding.