Fig. 8: aPVTCRF neurons mediate target-dependent synaptic transmission in the NAc in vitro.
From: A hypothalamic-thalamostriatal circuit that controls approach-avoidance conflict in rats
a Schematics showing viral injection site in aPVT and recording site in NAc in rat brain slices expressing ChR2-eYFP in aPVTCRF afferents. b, c Representative whole-cell recordings of a putative b medium spiny neuron (MSN, purple) and c cholinergic interneuron (CIN, red) showing responses to hyperpolarizing and depolarizing current steps (−300 and 200 pA, 500 ms). CINs were distinguished from MSNs by larger diameter cell bodies and rebound firing following a hyperpolarizing current step. d, e Representative examples of optically evoked excitatory postsynaptic currents in an d MSN and a e CIN prior to and following the application of the AMPA receptor antagonist NBQX. f Representative examples of optically evoked excitatory postsynaptic currents (EPSCs) in an MSN (purple) and a neighboring CIN (red) recorded sequentially (LED duration: 1 ms). g (Left) Summary data quantifying optically evoked EPSC amplitudes in sequentially recorded pairs of MSNs and CINs (n = 9 pairs, three rats), indicating larger EPSCs in MSNs (paired Student’s t test, P = 0.038, t = 2.483). (Right) For the same pairs, graph plots EPSCCIN/EPSCMSN ratios. h Representative synaptic responses in sequentially recorded MSN (purple) and a CIN (red) evoked by a 20 Hz stimulus train. Responses are normalized to the amplitude of EPSC1. i Summary data quantifying EPSC amplitudes of MSNs (purple) and CINs (red) normalized to EPSC1 (n = 9 pairs). Short-term synaptic plasticity (quantified as EPSC8–10/EPSC1) showed significant target-dependent differences (MSN: 0.95 ± 0.17; CIN: 2.19 ± 0.22, paired Student’s t test, P = 0.0014, t = 4.79). Scale bars: 500 µm. Data are shown as mean ± SEM. Blue bars indicate the timing of LED stimuli.
