Abstract
We have previously shown that glutamate induces the translocation of drebrin and F-actin from dendritic spines to the parent dendrites. We demonstrated that postsynaptic Ca2+-influx via NMDA receptor was needed to the translocation. However, the mechanisms of the translocation have not been clarified yet. In the present study, we analyzed the effect of blebbistatin, an inhibitor of myosin II ATPase activity, on the glutamate -induced translocation in cultured hippocampal neurons. We prepared the low-density cultures of rat hippocampal neurons from 18-day embryo. After 21 days in vitro, we pretreated the cultured neurons with 100 μM blebbistatin for 60 min. Then, we applied 100 μM glutamate for 10 min and analyzed the location of drebrin and F-actin immunohistochemically. Blebbistatin completely inhibited the glutamate-induced translocation of drebrin and F-actin. These data demonstrate that myosin II activity is required for translocation of drebrin and F-actin from dendritic spines to parent dendrites in hippocampal neurons. [Jpn J Physiol 55 Suppl:S154 (2005)]
