An automated method for the evaluation of jumping activity in mice. Effects of clonidine on morphine withdrawal

A fast and simple method for the evaluation of jumping activity in morphine-abstinent mice is described. Number, height and distribution of jumps were recorded automatically by means of photocell detectors coupled to a programmable recorder. The effects of the alpha 2-agonist clonidine on morphine withdrawal jumping were also studied. This drug did not significantly modify the total number of jumps performed by morphine-withdrawn mice, but decreased the intensity of the jumps and modified their distribution. It is concluded that the simultaneous evaluation of the three variables mentioned can provide complementary information about the actions of drugs on morphine withdrawal jumping; in this way, the methodology described is useful for performing this kind of study.