Expression of Hcn subunits in the vestibular neuron cell bodies. (A) Quantitative RT-PCR was used to estimate the mRNA expression level/vestibular ganglion for each of the four Hcn subunits from a pool of 10 vestibular ganglia at P8. Error bars represent SEM from six technical replicates. (B) The percentage of Neurofilament-200–positive vestibular neuron cell bodies that expressed HCN1, -2, or -4. The numbers of cells counted for each HCN subunit are shown at the bottom. (C–E) Representative immunolocalization images for HCN1 (C), HCN2 (D), and HCN4 (E) wild-type vestibular neuron cell bodies (P8). Images of these sorts were used to generate the counts shown in B. Bars, 20 µm.