Ma_1998_Brain.Res_793_112

The possible role of a hippocampal afterdischarge (AD) episode in eliciting locomotor movements was evaluated in freely moving rats. Electrical stimulation of either the ventral subiculum (VSB) or the hippocampal CA1 region evoked an AD of 6-50 s in duration, which was followed by an increase in locomotor activity. Similar results were also observed after unilateral injection of N-methyl-d-aspartic acid (NMDA, 0.25 microg or 1 microg), a glutamate receptor agonist, into the VSB. Locomotor activity was not observed when either electrical or chemical stimulation of the VSB, or electrical stimulation of the CA1 region did not elicit an AD. In addition, the duration of the AD was positively correlated with the number of locomotor movements induced by stimulation of VSB or CA1 region. It is suggested that the hippocampal/subicular AD may be a necessary condition to induce locomotor activity by either chemical or electrical stimulation of the hippocampus in rats.