Figure 1.
Different corticostriatal response in D1 or D2 eGFP medium spiny neurons (MSNs) from BAC mice. (A,B) Families of subthreshold and suprathreshold corticostriatal synaptic responses for representative D1- (red traces) and D2- (green traces) MSNs obtained from BAC transgenic mice striatum. Insets show biocytin-filled recorded cells and green fluorescent protein positive (GFP+) accompanying cells (insets). Yellow color of recorded cells indicate D1- (A) and D2-eGFP-positive cells (B), respectively (superimposition). Notice that D1-MSNs suprathreshold response is more prolonged and generates more action potentials whereas D2-MSNs response only display an initial burst of high frequency firing. (C,D) Area under response is smaller in D2-MSNs, as well as half-widths (F–H) Histograms summarize measurements in neuronal samples (half-widths and areas under responses): n = 55 D1-MSNs and n = 50 D2-MSNs. Differences were significant. (E) Traces at a slower sweep (1–3) illustrate frequency of discharge in D1- (1), D2-MSNs (2) as well as intrinsic autoregenerative responses in D2-MSNs. (I) Firing frequency was higher in D2-MSNs.