一份报告说，细胞膜电位的微小差异可能改变它与其他细胞通信的方式。这项研究可能有助于理解导致中风和心律不齐的心脏和中枢神经系统疾病的机制。细胞使用称为间隙连接的细胞间通道，在许多种类的细胞（包括心血管细胞和神经系统细胞）之间把代谢物和信号传导分子从一个细胞的内部运输到另一个细胞的内部。通过细胞间隙的信号传导协调正常组织的细胞活动，而缺氧和缺血等病理症状可能改变这种信号传导行为。
Nicolas Palacios-Prado和Feliksas Bukauskas发现，由不同的连接蛋白组成的通道——包括那些构成了血管、心脏和神经系统的细胞间隙的通道——的行为就像控制电和化学信号的对电压敏感的阀门。这些阀门允许定向的、细胞对细胞的电信号传导，还能控制代谢细胞通信。这组作者发现，这种通信可以通过跨膜电位的微小变化或者突发的高频动作电位加以调控。（生物谷Bioon.com）
生物谷推荐原始出处：
PNAS August 24, 2009, doi: 10.1073/pnas.0901923106
Heterotypic gap junction channels as voltage-sensitive valves for intercellular signaling
Nicolas Palacios-Prado and Feliksas F. Bukauskas,1
Gap junction (GJ) channels assembled from connexin (Cx) proteins provide a structural basis for direct electrical and metabolic cell–cell communication. By combining fluorescence imaging and dual whole-cell voltage clamp methods, we demonstrate that in response to transjunctional voltage (Vj) Cx43/Cx45 heterotypic GJs exhibit both Vj-gating and dye transfer asymmetries. The later is affected by ionophoresis of charged fluorescent dyes and voltage-dependent gating. We demonstrate that small differences in resting (holding) potentials of communicating cells can fully block (at relative negativity on Cx45 side) or enhance (at relative positivity on Cx45 side) dye transfer. Similarly, series of high frequency Vj pulses resembling bursts of action potentials (APs) can fully block or increase the transjunctional flux (Jj) of dye depending on whether pulses are generated in the cell expressing Cx43 or Cx45, respectively. Asymmetry of Jj-Vj dependence is enhanced or reduced when ionophoresis and Vj-gating act synergistically or antagonistically, whereas single channel permeability (Pγ) remains unaffected. This modulation of intercellular signaling by Vj can play a crucial role in many aspects of intercellular communication in the adult, in embryonic development, and in tissue regeneration.
