Figure 3. R2HBJJ inhibited the contractile response induced by carbachol in guinea-pig tracheal strip.

Carbachol (1 µM) was used to induce contractile response. After that, the indicated concentrations of R2HBJJ or atropine were added cumulatively into the organ bath and the inhibitory concentration responses against carbachol-induced contraction were obtained. The values were expressed as percentages of the maximum contractile response in the absence of any antagonist. Each point represented the mean ± SD of five independent experiments.