Fig. 6. Effect of thapsigargin 100 nm pretreatment: quantitative analysis of average neuronal Ca2+cytduring (A ) 0–10 min, and (B ) 10–60 min, exposure to LA. First letter indicates LA treatment: L = lidocaine, B = bupivacaine, T = Tris control equimolar to lidocaine. Modifier indicates thapsigargin pretreatment:−Tps = no thapsigargin pretreatment; +Tps = with thapsigargin pretreatment. Note that these legend symbols are distinct from the symbols used over the bar graphs to indicate statistical significance (listed at end of next paragraph). Data without Tps are the same as in figs. 3 and 4, repeated here to facilitate comparison ±Tps. Bupivacaine 1.25% equipotent to 5% lidocaine was not tested because of solubility limits at pH 7.4. Since the purpose of these experiments was to determine the effect of Tps on the perturbation of Ca2+cytby LA, the only Tris control done for +Tps was equimolar to 5% lidocaine (i.e. , highest concentration) and is included for illustration only, not for statistical comparisons. Only statistical comparisons specific to Tps are shown on this graph: T =P < 0.001 +versus − Tps (same LA, concentration, time period); t =P < 0.01 +versus − Tps (same LA, concentration, time period); ##=P < 0.001 bupivacaine versus lidocaine (+Tps; same concentration and time period); #=P < 0.05 bupivacaine versus lidocaine (+Tps; same concentration and time period); R =P < 0.001 0–10 min versus 10–60 min (+Tps; same LA and concentration); shown only on 10–60 min graph.
