Disparate effects of pramipexole on locomotor activity and sensorimotor gating in Sprague-Dawley rats

► The behavioral effects of the D3 agonist, pramipexole (PPX) were tested in rats. ► PPX caused dose- and time-dependent biphasic changes in locomotor activity (LA). ► PPX-hyperactivity (min 50-90) was D2-dependent; PPX-hypoactivity (min 0-30) was not. ► PPX disrupted PPI at times corresponding to both PPX-hyper- and -hypoactivity. ► Disparate mechanisms regulate PPC effects on LA vs. PPI.