Cyclosporine-A reduces spontaneous place preference in adult rats

Cyclosporine-A (CsA) and its analogues have been shown to directly alter locomotor activity. The present study examined CsA effects on spontaneous preferential behavior in adult rats, using a two-shuttle compartment box. The initial preference (>450 s staying time) of the animal for one compartment was measured at pre-conditioning session (900 s). During conditioning session (one 60-min session per day for 6 consecutive days), the animal was alternately injected with CsA (5, 10, 20 and 30 mg/kg per day, i.p.) and vehicle, and its movement restricted to the preferred compartment and the other compartment, respectively. At post-conditioning session (900 s), animals were allowed to freely explore the box. Animals that were treated with 10 mg/kg CsA significantly spent less staying time in the preferred compartment, while those that received other CsA doses displayed a trend of decreased staying time in the preferred compartment. The present data demonstrate that CsA antagonized the spontaneous preferential behavior of animals, and warrant investigations on the drug's utility in altering other preferential behaviors (e.g. drug addiction, alcohol abuse).