Biology Project Abstract
3-D NEURONS: MECHANISMS OF RAPID ACTION POTENTIAL FIRING IN INHIBITORY INTERNEURONS OF THE HIPPOCAMPUS
Presenters:
Amit A. Mahadevia, Illinois Mathematics and Science Academy, 1500 West Sullivan Road, Aurora, IL, 60506; amitm@imsa.edu
Amit Nathani, Illinois Mathematics and Science Academy, 1500 West Sullivan Road, Aurora, IL, 60506; anathani@imsa.edu
Mentors:
Ms. Alexia Metz, Northwestern University, 2153 North Campus Dr., Evanston, IL, 60208-3520; 847-467-2734; 847-491-5211; a-metz1@northwestern.edu
Mr. Alex Roxin, Engineering Sciences and Applied Mathematics Technological Institute, 2145 Sheridan Road, Evanston, IL, 60208-3125; a-roxin@northwestern.edu
Dr. Nelson Spruston, 2153 North Campus Drive, Evanston, IL, 60208-3520; 847-869-2565; 847-491-5211; spruston@northwestern.edu
Abstract:
Action potentials are the primary mode of communication within the nervous system. They are propagated when enough current depolarizes the neuronal membrane, exceeding the cell’s specific threshold. Within the hippocampus, there is a variety of interneurons that function in local processing. However, little is known about the correlation between the properties of the cell and their firing behavior. To investigate this, we used transverse hippocampal slices of Wistar rats to perform current-clamp experiments, or electrically record cell behavior. We investigated the active properties of hippocampal inhibitory interneurons by causing these cells to fire action potentials and recording their behavior. Passive properties, which include membrane resistance, capacitance and resting potential, are properties of the neuron that influence action potential firing. For example, one way in which the properties affect action potential firing is that a high membrane resistance lowers the amount of current needed to obtain threshold. We measured these passive properties by electrically recording subthreshold behavior. The morphology of the interneurons was reconstructed in three dimensions (NeuroLucida), to accurately reproduce the physical properties of the cell. After reconstruction, the active properties, passive properties, and morphology were combined into a mathematical model (NEURON). This model will be useful in accurately predicting cell behavior.