What resolves this contention: Reiner et al 2004 in rat report differential cor…

What resolves this contention: Reiner et al 2004 in rat report differential cortical input to direct vs indirect MSNs (IT- vs PT-type biased), implying differential excitatory innervation of the two pathways. Doig et al 2010 in mouse find that the proportion of cortical (VGluT1) and thalamic (VGluT2) terminals onto D1- and D2-MSNs is the same. The disagreement turns on whether direct- and indirect-pathway MSNs are differentially innervated by glutamatergic inputs at the population level. / Finally, we combined selective BDA labeling of IT-type or PT-type terminals with immunolabeling for D1 or D2, and found that IT-type terminals were twice as common as PT-type on D1+ spines, whereas PT-type terminals were four times as common as IT-type on D2+ spines. / We found that the proportion of synapses formed by terminals derived from the cortex and thalamus was similar for both direct and indirect pathway MSNs.