Involvement of presynaptic N-methyl-D-aspartate receptors in cerebellar long-term depression
Involvement of presynaptic N-methyl-D-aspartate receptors in cerebellar long-term depression
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DOI：
10.1016/s0896-6273(01)00568-2
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发表时间：
2002-01-03
期刊：
影响因子：
16.2
通讯作者：
Ascher, P
中科院分区：
文献类型：
--
作者：
Casado, M;Isope, P;Ascher, P
在平行纤维 (PF) 和浦肯野细胞 (PC) 之间的小脑突触中，兴奋性突触电流的长期抑制 (LTD) 被认为与 N-甲基-D-天冬氨酸 (NMDA) 受体激活无关，因为 PC 缺乏 NMDA 受体。然而，我们现在报道，LTD 被作用于 PF 突触前 NMDA 受体的 NMDA 受体拮抗剂抑制。当输入仅限于单根光纤时，仍然可以观察到这种效应。因此，LTD不需要多个输入的空间整合。相反，它涉及时间整合，因为可靠的 LTD 感应需要 PF 紧密连续地激发两个动作电位。这意味着 LTD 将选择性地抑制对突触前动作电位爆发的反应。
At the cerebellar synapses between parallel fibers (PFs) and Purkinje cells (PCs), long-term depression (LTD) of the excitatory synaptic current has been assumed to be Independent of the N-methyl-D-aspartate (NMDA) receptor activation because PCs lack NMDA receptors. However, we now report that LTD is suppressed by NMDA receptor antagonists that act on presynaptic NMDA receptors of the PFs. This effect is still observed when the input Is restricted to a single fiber. Therefore, LTD does not require the spatial integration of multiple inputs. In contrast, it involves a temporal integration, since reliable LTD induction requires the PFs to fire two action potentials in close succession. This implies that LTD will selectively depress the response to a burst of presynaptic action potentials.