Two
proton-gated channels, acid-sensing ionic channel (ASIC)
and dorsal root ASIC (DRASIC), are known
to be expressed by sensory neurons. These types of channels
are of interest because low pH causes pain.
ASIC Beta, a splice variant of ASIC, is found only in a subset
of small and large diameter sensory neurons
and is absent from sympathetic neurons or the central nervous
system.
Reference:
Chen,
C. C., England, S., Akopian, A. N., and Wood, J. N. (1998).
A sensory
neuron-specific, proton-gated ion channel. Proc Natl Acad
Sci U S A 95, 10240-5.