Fig. 2.

Inhibition of RTX-induced desensitization of rat DRG neurons by capsazepine. Cells were incubated in the presence of 250 pm RTX and different concentrations of capsazepine for 6 hr. Cells were then washed three times with serum-free DMEM containing 0.25 mg/ml BSA to remove the above compounds and were then challenged with 200 nm RTX to induce ⁴⁵Ca uptake (▪). Cells not treated with either RTX or capsazepine (○, control) or treated with only 250 pmRTX for 6 hr (□) are shown as control values. Points represent mean values from sets of eight determinations in a single experiment; error bars indicate SEM. The theoretical curve was calculated by fitting the measured values to the Hill equation. Two additional experiments yielded similar results.