Fig. 5.
Immunocytochemistry shows CaV2.3 channels expressed in muscle afferent neurons. A: the upper four images show sensory neurons stained with both voltage-gated sodium (NaV) 1.8 and CaV2.3 antibodies. The bright-field (left) image shows the three neurons, and the DiI panel (right) shows the one labeled muscle afferent neuron in this field. All three neurons were positive for both NaV1.8 and CaV2.3. The white bar in the bright-field image indicates 50 μm. The lower four images show NaV1.8 and CaV2.3 controls along with bright-field (left) image and the DiI image showing one labeled muscle afferent neuron. B: there is no correlation between CaV2.3 label intensity and muscle afferent neuron size. The threshold line was determined from measurement of Cntl muscle afferent neurons (e.g., lower images in A). The units for the Y-axis are arbitrary fluorescence units. C: comparison of CaV2.3 label intensity vs. that of NaV1.8 in muscle afferent neurons. The threshold lines were determined from Cntl muscle afferent neurons. Only one CaV2.3-positive muscle afferent neuron was negative for NaV1.8.