Nicotine Induces An Increase In Excitatory Junctional Potential Amplitude At The Crayfish Neuromuscular Junction And Desensitization After Prolonged Nicotine Exposure

Abstract

The objective of our study was to establish the relationship between nicotine exposure and excitatory junctional potential (EJP) amplitude at the crayfish neuromuscular junction (NMJ). We isolated crayfish dorsal lateral tail extensor muscles and recorded the EJP amplitude in standard crayfish ringers solution and ringers solution containing nicotine. We found that applications of 6 and 12 mM nicotine to the crayfish NMJ were sufficient to enhance EJP amplitude. We also found evidence for desensitization after prior exposure to nicotine. These results suggest the short term effects of nicotine enhance EJP amplitude, whereas the long-term effects are desensitizing.