Figure 2.

Plasma concentration of tolbutamide after a 20 mg/kg oral dose of tolbutamide to control, ethanolic extract of Andrographis paniculata- (APE-) pretreated, and andrographolide-pretreated rats. Rats were given daily a 2 g/kg dose of APE (○) or 50 mg/kg andrographolide (△) for 5 days before the tolbutamide was given. Control rats received 10 mL/kg of 0.5% aqueous methyl cellulose daily (vehicle, ⚫) for 5 days. Values shown are the mean ± SD, n = 5. The significance of the difference among group means was determined by one-way ANOVA followed by Tukey's test. Values of treatments not sharing the same letter differ significantly, P < 0.05.