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

Figure 1 Role of opioid μ-receptors in gastrointestinal tract using charcoal as an indicator. The data represent the distance (A) and time (B) for the transit of charcoal. Data represent the mean ± SEM of eight animals. ^bP < 0. 01 vs the distilled water (vehicle)-treated control.

Figure 2 Inhibitory effect of cyprodime or naloxonazine on relaxation induced by loperamide (10 μmol/L) in isolated ileum 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. ^bP < 0.01 vs the distilled water (vehicle)-treated control.

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.