Nonopiate effects of alpha-neo-endorphin on mouse behavior using multi-dimensional behavioral analyses

The effects of alpha-neo-endorphin on mouse behavior were investigated by using a multi-dimensional behavioral analyser (Animex II) which classifies animal's movements into nine degrees. The intracerebral injection of alpha-neo-endorphin (30 micrograms) significantly decreased the 1/1, 1/2 and 1/4 sizes of movement (linear locomotion and rearing) within 15 min after injection. None of the effects were significantly affected by naloxone even at high doses. The results suggest that a behaviorally active site within the alpha-neo-endorphin sequence is capable of quite potent but nonopiate effects.