Fig. 3. TA and DOP negate the effect of EPI in increasing the intracellular Ca++ level. (A) The effects of TA and DOP on a₁-AR were examined in LNCAP cells. The cells were treated with the Fluo-8 NW and incubated for 1 h. TA, DOP and PTL (positive control) were added separately to the LNCAP cells at concentration 50 mg/ml for 5 min. Then, EPI (50 mg/ml) was added and incubated further for 12 min and the intracellular Ca++ level of LNCAP cells was measured every 3 min. Treatment with EPI alone caused an oscillation of intracellular Ca++ level of LNCAP cells while in the presence of TA, DOP and PTL, the intracellular Ca++ levels were similar to the control (H₂O). The addition of TA, DOP and PTL without EPI did not show any significant effect on intracellular Ca++ level. The data are shown in relative fluorescence unit (RFU). (B) The treatment of TA, DOP and PTL (50 mg/ml) with and without EPI (50 mg/ml) did not show significant effect on viability of the LNCAP cells. The addition of EPI (50 mg/ml) alone increased the LNCAP cells viability. Each data point is the mean value ± SEM from minimum 3 independent replications, *p<0.05; **p<0.01, data were analyzed using Students t-test.