Department of Biology, Boston University, 5 Cummington St., Boston, MA 02215, USA.
Curr Opin Neurobiol. 2011 Apr;21(2):291-8. doi: 10.1016/j.conb.2011.01.001. Epub 2011 Feb 2.
AMPA receptors (AMPARs) are heterotetromeric complexes composed of GluA1-4 subunits. They are glutamate-gated channels traditionally considered solely as ion carriers for postsynaptic depolarization. However, the existence and dynamic regulation of GluA2-lacking, calcium-permeable AMPARs (Cp-AMPARs) enable these special receptors to serve also as signaling molecules presumably via calcium influx. Recent studies have implicated Cp-AMPARs in several types of synaptic plasticity, including homeostatic synaptic regulation and Hebbian synaptic plasticity. Cp-AMPARs are usually expressed transiently at an early stage of synaptic plasticity, but are then replaced with normal GluA2-containing receptors, indicating a role for Cp-AMPARs in induction, rather than the maintenance, of synaptic plasticity.
AMPA 受体（AMPARs）是由 GluA1-4 亚基组成的异四聚体复合物。它们是谷氨酸门控通道，传统上被认为仅仅是作为突触后去极化的离子载体。然而，缺乏 GluA2、可通透钙离子的 AMPARs（Cp-AMPARs）的存在和动态调节使这些特殊的受体也能够作为信号分子，可能通过钙离子内流发挥作用。最近的研究表明，Cp-AMPARs 参与了几种类型的突触可塑性，包括同源性突触调节和赫布型突触可塑性。Cp-AMPARs 通常在突触可塑性的早期阶段短暂表达，但随后被正常含有 GluA2 的受体取代，这表明 Cp-AMPARs 在诱导而不是维持突触可塑性中发挥作用。
