Figure 1. Features of a layer V MC.

A, 3-D computer reconstruction (soma and dendrites are in red, axon in blue, boutons marked with dots). Note bitufted morphology, ovoid somata, axon targeting layers I, IV and V and downward dendritic projections. B, photo of spiny boutons on MC axons (arrows). C, EM image of MC boutons in layer I. D, classical accommodating discharge to sustained somatic current injections. E, single-cell RT-PCR results: agarose gel showing the expression of mRNAs encoding for the CaBPs (calbindin, CB; parvalbumin, PV; and calretinin, CR); the neuropeptides (neuropeptide Y, NPY; vasoactive intestinal peptide, VIP; somatostatin, SOM; cholecystokinin, CCK); the voltage-activated K⁺ channels (Kv1.1, Kv1.2, Kv1.4, Kv1.6, Kv2.1, Kv2.2, Kv3.1, Kv3.2, Kv3.3, Kv3.4, Kv4.2 and Kv4.3) and their auxiliary subunits (Kvβ1 and Kvβ2); the K⁺/Na⁺ permeable hyperpolarization-activated ion channels (HCN1, HCN2, HCN3 and HCN4); the Ca²⁺-activated K⁺ channel (SK2); the voltage-activated calcium channels (Caα1A, Caα1B, Caα1G and Caα1I) and their auxiliary subunits (Caβ1, Caβ3 and Caβ4) and the ubiquitous protein GAPDH. See Table 1 for the lists of the primer pairs included into the different multiplexes, the name and accession number of the genes amplified and the length of the PCR product.