Table 4

Comparison of VR binding and vanilloid-induced 45Ca2+uptake in sensory (DRG) neurons, mast cells, and glioma cells

NeuronsMast CellsGlioma Cells
Calcium influxYesYesYes
45Ca2+ uptake by capsaicin (potency, nM)
  Inhibition by capsazepine29031040
  Block by ruthenium red800980690
45Ca2+ uptake by resiniferatoxin (potency, nM)
  Inhibition by capsazepine325290N.D.
  Block by ruthenium red790910N.D.
[3H]RTX bindingYesNoNo
 Affinity (K d, nM)0.04N/AN/A
 Inhibition by capsaicin (K i, nM)4,900N/AN/A
 Inhibition by capsazepine (K i, nM)4,000N/AN/A
 Inhibition by ruthenium red (IC50, nM)14N/AN/A
  • N.D., not determined; N/A; not available. Data are from Ács et al., 1996b, 1997 (DRG neurons), Bı́ró et al., 1998a(mast cells) and b (glial cells), respectively.