Biology: Memory at the Frog Neuromuscular Junction
Hannah Geiser, Sophomore
Dr. Rich Manalis, Dr. James Miller
How do you remember how to ride a bike? What really happens in your brain that you can recall eating a piece of pie a year ago? This projectís goal was to develop an undergraduate lab using the frog gastrocnemius muscle to demonstrate the simplest form of memory. Since brain synapses are not convenient to work with, we have studied the frog neuromuscular junction as an alternative. However, neuromuscular junctions have all-or-none responses, so this project looks at making the synapse reliably exhibit facilitation. Variations using temperature, high magnesium/ low calcium ringerís solutions, d-tubocurarine chloride, and high frequency stimulation were all tested for reproducibility. Dissecting a gastrocnemius in a tray of 2.5 mM Mg and 1.0 mM Ca and letting the solution diffuse for 90 min before applying dual pulses appeared to get the most reliable facilitation.