Figure 8.
Evaluation of the responses to chemical agonist of thermo-TRP channels of cold-sensitive neurons from sham and injured mice. A, Protocol in calcium imaging used to evaluate the responses to cold, menthol (100 μm), cold plus menthol, AITC (100 μm; TRPA1 agonist), and capsaicin (200 nm; TRPV1 agonist) in cold-sensitive neurons from sham and CCI animals. A, The CSN corresponds to a LT control neuron, which is insensitive to AITC but sensitive to capsaicin. B, Pie plots summarizing the percentage of menthol-, AITC-, and capsaicin-sensitive CSNs from sham and CCI animals. Menthol responses included an increase in the [Ca2+]i at 34°C or a shift (>1°C) in the cold threshold toward higher temperatures. C, Bar histograms represent the maximal response to menthol at 34°C and/or cold plus menthol (left panel), AITC at 34°C (central panel), and capsaicin at 34°C (right panel) in CSNs responding to these agonists, isolated from sham (black bars) and CCI animals (red bars). *p = 0.045 (F test).