A novel method for automatic pharmacological evaluation of sucrose preference change in depression mice.

Sucrose preference test (SPT) is a most frequently applied method for measuring anhedonia, a core symptom of depression, in rodents. However, the method of SPT still remains problematic mainly due to the primitive, irregular, and inaccurate various types of home-made equipment in laboratories, causing imprecise, inconsistent, and variable results. To overcome this issue, we devised a novel method for automatic detection of anhedonia in mice using an electronic apparatus with its program for automated detecting the behavior of drinking of mice instead of manual weighing the water bottles. In this system, the liquid surface of the bottles was monitored electronically by infrared monitoring elements which were assembled beside the plane of the water surface and the information of times and duration of each drinking was collected to the principal machine. A corresponding computer program was written and installed in a computer connected to the principal machine for outputting and analyzing the data. This new method, based on the automated system, was sensitive, reliable, and adaptable for evaluation of stress- or drug-induced anhedonia, as well as taste preference and effects of addictive drugs. Extensive application of this automated apparatus for SPT would greatly improve and standardize the behavioral assessment method of anhedonia, being instrumental in novel antidepressant screening and depression researching.