Selective Activation of hTRPV1 by N-Geranyl Cyclopropylcarboxamide, an Amiloride-Insensitive Salt Taste Enhancer
Figure 2
Calcium responses in hTRPV1-expressing cells stimulated with capsaicin (Cap) and NGCC.
(A) Cells expressing hTRPV1 were loaded with Fura-2 AM and Ca2+ images were obtained at 0 and 60 s after stimulation with Cap or NGCC. The non-specific blocker of TRP channels, RR (30 µM), and the specific TRPV1 antagonist, CPZ (5 µM), were added to test the selectivity of Cap and NGCC. Representative ratiometric images are shown after treatment with Cap and NGCC. (B) As a control, the Ca2+ response was monitored in non-hTRPV1-expressing HEK 293T cells treated with Cap or NGCC. (C) The effects of Cap or NGCC treatment were quantified using Calcium-4 in a cell-based assay in the presence or absence of 30 µM RR or 5 µM CPZ. Experiments were repeated in triplicate and data points represent the means ± SEM (n = 3).