Nitric Oxide Plays a Significant Role as a Retrograde Messenger that Causes Long-Term Facilitation at the Crayfish Neuromuscular Junction

Abstract

Nitric oxide (NO) is a compound that acts as a retrograde messenger in a variety of organisms. It also plays a role in the strengthening of synapses and facilitation of synaptic plasticity. In our study, we asked whether NO plays a similar role in the crayfish neuromuscular junction. Our results indicate that NO does indeed act as a retrograde messenger that is produced in the postsynaptic muscle fiber and affects the presynaptic cell, increasing synaptic plasticity and causing long term facilitation. When NO production was chelated in the postsynaptic cell, EPSP amplitude decreased considerably, and when NO production was catalyzed, EPSP amplitude increased, supporting our hypotheses.