Figure 5: Extrasynaptic GluN2B-NMDARs mediate LTP under transient EAAT2 blockade.
From: Astrocytes gate Hebbian synaptic plasticity in the striatum
(a) The LTP induced under EAAT2 blockade for ΔtSTDP=±200 ms and ΔtSTDP=±500 ms was mediated by NMDARs, because it was prevented by D-AP5 (50 μM) application. (b) The LTP induced under transient EAAT2 blockade for ΔtSTDP=±200 ms was prevented by blocking postsynaptic NMDARs with i-MK801 (1 mM) applied intracellularly in the recorded MSN. (c) The inhibition of GluN2B-containing NMDARs with Ro25–6981 (10 μM) prevented the induction of LTP. (d) The inhibition of extrasynaptic NMDARs with memantine (10 μM) prevented LTP under transient EAAT2 blockade. Extrasynaptic GluN2B-containing NMDARs located on the postsynaptic MSN are thus required for the induction of LTP under transient EAAT2 blockade. Insets correspond to the mean of 60 EPSCs during baseline and at 1 h after STDP pairings. Error bars represent s.d. (except in bar graphs: s.e.m.). NS: not significant by one sample t-test.
