Description

Peripheral nerves supply the inputs and outputs that determine how we sense and respond to both the internal and external environments; for example, the vagus detects the function of the interval organs and supplies motor output controlling the heart and gastrointestinal tract and other organs. This perfusion chamber model is designed to test evoked nerve responses using electrical stimulation of one nerve end and electrophysiological recording of the opposite nerve end (15 to 25 mm nerve length); responses can be recorded from teased fiber bundles or the whole nerve. The dissected nerve of laboratory animals, for example, musk shrew, mouse, and rat, can be placed in the middle perfusion compartment and kept alive with oxygenated Krebs solution flowing through the input port and exiting by way of the two outflow ports (2 are used to ensure that the compartment will not overflow). The lateral stimulation and recording compartments contain holes for placement of fine wire electrodes, which can be guided to the top of the model for connections to the stimulator and recording equipment (e.g., high impedance head stage and amplifier system). The lateral compartments are sealed from the middle perfusion compartment by running the nerve under thin plastic gates coated with vacuum grease; gates are lowered into grooves that are built into the model. This project received funding support from the NIH SPARC Program, Award number = U18EB021772.