Figure 3.
Inhibition of GABAARs in the postsynaptic neuron only is sufficient to reverse STDP. A, Raw traces of 50 s recordings in the presence or absence of e-PTX (in D-AP5/CNQX) in a pair of MSNs recorded simultaneously, one with regular internal solution (neighboring MSN) and one with PTX inside the internal solution (i-PTX, 1 mm). Right panels, frequency and amplitude of IPSCs in the presence or absence of e-PTX and i-PTX (in D-AP5/CNQX). This shows that i-PTX blocks IPSCs as efficiently as e-PTX in MSNs. B, MSN paired recordings with one MSN recorded with control intracellular solution and a neighboring MSN recorded with i-PTX (1 mm), the two neurons being <50 μm away. Post-pre pairings induced LTD in i-PTX recorded MSNs, whereas LTP was observed in neighboring control MSNs (top graphs). Conversely, after pre-post pairings, LTP was observed in i-PTX MSN, whereas LTD was observed in control MSNs (bottom graphs).