Effects of Brugmansia arborea Extract and Its Secondary Metabolites on Morphine Tolerance and Dependence in Mice

Figure 4

Effects of different doses of Brugmansia arborea L. on the expression (a) and the acquisition (b) of morphine dependence. Mice were treated twice daily for 5 days with saline or 10 mg/kg morphine treatment. On the sixth day, withdrawal syndromes were precipitated by injection of 5 mg/kg naloxone, 2 h after the last morphine injection. BRU (0, 7.5, 15, and 30 mg/kg) was administered 30 min before each morphine injection (acquisition) or prior to naloxone injection (expression). The withdrawal symptoms are given as a summary of the frequency of these somatic signs: jumping, rearing, forepaw tremors, and teeth chatter. Significant differences: **𝑃<0.01, compared to control; ⁺𝑃<0.05, ⁺⁺𝑃<0.01, compared to morphine group.

(a)

(b)