Long Term Potentiation in Mouse Hippocampal Slices in an Undergraduate Laboratory Course.

Long-term potentiation (LTP) is thought to be a critical mechanism underlying learning and memory. Although LTP is now widely performed in neuroscience research laboratories and the theory behind it is taught in many undergraduate courses, it is rare for undergraduate students to have the opportunity to perform LTP experiments themselves. Here, we describe a series of two laboratory sessions in which upper level students learn how to perform LTP experiments in acute hippocampal slices from wild type mice. In Laboratory 1, students practice the techniques necessary to set up the experiments. These techniques include making solutions, pulling glass recording electrodes, performing brain removal, preparing hippocampal slices, and positioning electrodes in area CA1. For Laboratory 2, hippocampal slices are prepared in advance by the instructors. Students record LTP by stimulating the Schaffer collateral axons and recording postsynaptic field potential responses in the apical dendritic region of area CA1. Once the students determine appropriate stimulus strength, they collect baseline responses, deliver a tetanic stimulus, and then collect responses 10 and 30 minutes following tetanic stimulation. Students analyze the data in LabChart 7 (ADInstruments - North America, Colorado Springs, CO, 2011) and perform appropriate statistical tests to determine whether potentiation has occurred. These laboratory exercises provide a unique opportunity for students to gain an appreciation for the techniques that are fundamental to studies of neural electrophysiology and plasticity as evidenced through a learning assessment tool.