Octopamine Operates Through the cGMP Pathway at the Crayfish Neuromuscular Junction

Abstract

We studied the neurohormone octopamine, attempting to determine if the cGMP pathway is involved in the modulation of synaptic transmission by octopamine in Procambarus clarkii muscle cells. We applied a soluble guanylyl cyclase inhibitor (ODQ) along with octopamine in different combinations to the prepared crayfish and measured excitatory postsynaptic potential (EPSP) amplitudes of extensor muscles of crayfish. Our results support our hypothesis that cGMP is involved in the octopamine pathway, as application of ODQ decreased the effect of octopamine on EPSP amplitudes.