A new behavioral test for antidepressant drugs.

In 1977 Porsolt proposed a new behavioral test, using mice, for screening antidepressants. He stated that antidepressants selectively reduce the immobility of mice in a forced swimming situation. The test is useful, but lacks objectivity in its evaluation of immobility and does not successfully screen 'false positive' drugs. A new 'behavioral despair' test was thus designed involving a small water wheel set in a water tank. Mice placed on this apparatus turned the wheel vigorously but, when they abandoned attempts to escape from the water the wheel stopped turning. The number of rotations of the water wheel were counted. All antidepressants tested increased the number of rotations. However, tranquillizers, anticholinergics and antihistaminics were not effective. We suggest that this water wheel test is more appropriate as screening test for antidepressants than Porsolt's test with regard to both objectivity and specificity.