Send to

Choose Destination
Brain Res. 1994 Jul 18;651(1-2):143-7.

Potentiation of rabbit trigeminal responses to capsaicin in a low pH environment.

Author information

Division of Neurosurgery (L472), Oregon Health Sciences University, Portland 97201.


The sensitivity of 35 adult rabbit trigeminal ganglion neurons to low pH (pH 6.0), 10 microM capsaicin (CAP) and 10 microM capsaicin at low pH (CAP@pH6.0) was studied using voltage-clamp whole-cell recording techniques. Neurons responded to pH 6.0 with a transient inward current, followed by a more slowly activating (sustained) net inward current. Responses to capsaicin showed only a sustained current. Capsaicin caused an increase in membrane conductance, whereas responses to low pH were associated with either a net increase or decrease in conductance. A subset of neurons (n = 14) responded to CAP@pH6.0 with a sustained current which exceeded the sum of the peak sustained currents evoked by CAP and pH 6.0 applied singularly by approximately a factor of 4. The current was associated with a substantial increase in membrane conductance. The present results indicate that, in addition to a direct conductance activating effect, protons have the ability to enhance the current evoked by capsaicin.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center