肺动脉平滑肌细胞上的钙离子通道研究进展

Advanced knowledge of the calcium ion channels on the pulmonary artery smooth muscle cells

钙离子（Ca2＋）为肺动脉平滑肌细胞（PASMC）内至关重要的第二信史，其细胞内浓度的精细变化直接受到多种Ca2＋通道的调控。按照细胞内Ca2＋的来源，位于细胞膜上，调控细胞外Ca2＋进入细胞的通道称为钙内流通道，位于肌质网上调控内质网／肌质网内钙库的Ca2＋释放的通道称为钙释放通道。根据Ca2＋通道激活方式的不同，Ca2＋内流的通道主要分为电压依赖性Ca2＋通道（VDCC）和非电压操纵性Ca2＋通道（non-VDCC）。目前发现PASMC上表达的VDCC为CaVL 2L型通道，nonVDCC包括受体操纵性通道和钙库操纵性通道。PASMC上的钙释放通道主要包括三磷酸肌醇受体系统和雷诺定受体系统。这些Ca2＋通道通过对细胞内Ca2＋的精细调节，使PASMC对各种信号刺激发生反应。

Calcium ion （Ca2＋ ） is an extremely crucial second messenger in the pulmonary artery smooth muscle cells （PASMC）. The intracellular Ca2＋ concentration is finely regulated by multiple Ca2＋ channels. According to the source of intracellular Ca2＋ , those lie in the cellular membrane and permit the extracellular Ca2＋ to enter into cytoplasm are named as calcium entry channels, and those lie in the sarcoplasmic reticulum and release the Ca2＋ stored in it are called calcium release channels. According to pathway of activation, calcium entry channels are divided into voltage-operated Ca2＋ channels （VOCC） and non voltage dependent Ca2＋ channels （non-VOCC）. The CaV 1.2 group or L-type VDCC, receptoroperated and store-operated non-VDCC have been found expressed in the PASMC. The calcium release channels mainly include inositol 1,4,5-trisphosphate receptor and Ryanodine receptor. Through the fine adjustment of all these Ca2＋ channels, the PASMC react to various stimulus signals.