Fig. 3.

Electrophysiology experiments demonstrate increased current through TRPV1. A, whole-cell patch-clamp experiments using HEK293-TRPV1 cells show that coapplication of 10 μM MRS1477 results in a 2-fold increase in the peak current activated by 200 nM capsaicin. The action of MRS1477 is rapid and reversible; it does not require preincubation and can be washed out. B, statistical analysis of peak currents shows that this increase is highly significant (P < 0.01). C, voltage-ramp experiments show the generalized enhancement of capsaicin-activated currents with no apparent change in the reversal potential of the current. In the absence of both capsaicin and MRS1477 (control), there was no measurable current. D, the enhancement is more important at negative holding potentials; the difference is significant when the extreme values of the holding potentials examined are compared.