Sodium Nitroprusside Decreases EPP Facilitation and Increases EPP Amplitude at the Crayfish Neuromuscular Junction

Abstract

The objective of our research was to determine whether nitric oxide (NO) affects neurotransmission and synaptic facilitation at the crayfish neuromuscular junction. To determine the effects of NO, we applied sodium nitroprusside (SNP) which releases NO in solution. We measured EPP amplitudes and facilitation at low and high-stimulus delay intervals (20 ms and 100 ms) for 20 minutes under control, experimental and wash conditions. Our results showed that SNP decreased the facilitation and increased the amplitude of EPPs at the crayfish neuromuscular junction. These results suggest that NO affects both neurotransmission and synaptic plasticity. In addition, the analysis of our experimental and wash condition data shows that SNP has reversible effects on EPP facilitation and irreversible effects on EPP amplitude.