Table 1.

Dendritic dimensions of reconstructed D1 and D2 MSNs

D1 MSN (n = 15)D2 MSN (n = 16)
Branch orderNumberLength (μm)NumberLength (μm)
1° Dendrite7.8 (±0.6)24.8 (±1.8)5.9 (±0.4)29.9 (±2.7)
2° Dendrite12.4 (±1.0)48.5 (±3.9)9.9 (±0.8)47.7 (±3.6)
3° Dendrite15.8 (±1.3)55.1 (±3.9)11.5 (±1.0)57.9 (±3.4)
4° Dendrite12.7 (±1.1)59.8 (±4.2)8.3 (±1.1)60.9 (±8.5)
5° Dendrite6.9 (±0.9)59.9 (±5.9)6.3 (±0.8)56.0 (±4.1)
6° Dendrite4.4 (±0.8)59.7 (±4.7)4.9 (±0.7)58.9 (±10.3)
7° Dendrite5.8 (±1.2)47.2 (±18.3)5.0 (±0.6)58.2 (±14.2)
Total tree471.8378.8
  • Dendritic segments of 15 D1 and 16 D2 reconstructed MSNs were compared with respect to average number per neuron and segment length (reported as mean ± SEM). The absolute number of segments per cell was significantly higher in D1 MSNs than in D2 MSNs for 1–4° branch orders, but not significant once normalized to the number of primary dendrites. The total length of a dendritic tree emerging from a single primary dendrite was not significantly different between D1 and D2 MSNs. The space occupied by D1 MSNs was significantly larger, whereas that occupied by a D1 MSN dendritic tree was not significantly different from that of a D2 MSN. The total convex hull surface for D1 MSNs was significantly larger than D2 MSNs (D1 MSN, 105.7 mm2; D2 MSN, 89.6 mm2; p < 0.05), although the area per primary dendrite was not different (D1 MSN, 8.5 mm2; D2 MSN, 12.3 mm2).