THE EFFECTS OF MK801 ON PLACE CONDITIONING

The appetitive properties of MK801 were investigated using the conditi oned place preference paradigm. Male Sprague-Dawley rats received cond itioned place preference training for a four-day period. The condition ing box consisted of three chambers with distinctive visual and tactil e cues, separated by removable doors. On alternating days rats receive d MK801 (0.05, 0.1, 0.25, 0.5 and 0.75 mg/kg) paired with one side of the chamber and saline paired with the other side. On the fifth day, r ats were placed in the center chamber and the time spent in each chamb er, as well as entries into each chamber were recorded by a trained ob server. MK801 produced a conditioned place preference for side paired with drug for the four highest doses. Contrary to previous findings, t hese results indicate that MK801 is appetitive at doses higher than ha s previously been assumed.