FIG 7.

Anidulafungin induced the PTV in a manner dependent on external and internal Ca²⁺ concentrations. (A) In Ca²⁺-containing buffer solution, anidulafungin induced a prolonged rise in the PTV that reached more than 200% of the basal PTV. Under long-term exposure, we observed a decline in the PTV. (B) In Ca²⁺-free buffer solution, the anidulafungin-induced rise in the PTV was reduced to approximately 150% of the basal PTV. Still, this rise in the PTV was prolonged and showed a slow decay during the exposure period. (C) Inhibition of ryanodine receptors using ryanodine in a molecular range (40 μM) reduced anidulafungin-activated PTV. (D) Anidulafungin induced a significant increase of the PTV in Ca²⁺-containing or Ca²⁺-free buffer solutions; however, the increase in the PTV was significantly lower in the Ca²⁺-free solution. The inhibition of the PKA signal transduction pathway using H-89 did not prevent an anidulafungin-induced rise in the PTV, but ryanodine prevented the anidulafungin-induced rise in the PTV (horizontal bars in experimental recordings present exposure periods of defined pharmacological agents; n, number of individual experiments; ns, not significant; time scale bars are present in all individual panels; *, P < 0.05; **, P < 0.01; ***, P < 0.001; Mann-Whitney U test).