Synergistic Effect of Ferulic Acid and Z-Ligustilide, Major Components of A. sinensis, on Regulating Cold-Sensing Protein TRPM8 and TPRA1 In Vitro

Figure 3

Isobolograms of combination of ferulic acid with Z-ligustilide in inhibiting response to agonists. The individual doses of ferulic acid and Z-ligustilide to achieve 90% (straight line) inhibition (Fa = 0.90), 75% (hyphenated line) inhibition (Fa = 0.75), and 70% (crosses) inhibition (Fa = 0.70) were plotted on the -axes and -axes. Combination index (CI) values calculated by Calcusyn software are represented by points above (indicating antagonism) or below the lines (indicating synergism).

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