The mechanosensitive cell line ND-C does not express functional thermoTRP channels

The molecular basis of mechanosensation in sensory neurons has yet to be defined. We found that ND-C cells, a hybrid cell line derived from neonatal rat DRG neurons, express mechanosensitive ion channels, and provide a useful expression system for testing candidate mechanosensitive ion channels. ND-C cells retain some important features of DRG neurons such as the expression of TTX-sensitive Na+ and acid-activated currents as well as the ability to respond to mechanical stimulation with cationic currents sensitive to the analgesic peptide NMB1. ND-C cells do not respond to agonists of the ‘thermoTRP’ channels, suggesting that these channels are not responsible for MA currents in these cells and DRG neurons. Furthermore, transfecting ND-C cells with the candidate mechanotransducer channel TRPA1 does not increase MA current amplitudes, despite TRPA1 being functionally expressed at the plasma membrane. This correlates well with the fact that all types of MA currents can be recorded from TRPA1-negative DRG neurons.