Opiate-induced constipation related to activation of small intestine opioid μ2-receptors

Figure 3 Effect of stevioside on the tone of isolated ileum strips contracted with 1 μmol/L acetylcholine. Data represent the mean ± SEM of the percentage changes in the acetylcholine (ACh)-induced tonic contraction of ileum from eight animals. ^aP < 0.05 vs the distilled water (vehicle)-treated control, shown in the first column.