Electrotonic transmission within pericyte-containing retinal microvessels.
Electrotonic transmission within pericyte-containing retinal microvessels.
复制标题
含有周细胞的视网膜微血管内的电紧张传输。
DOI：
10.1080/10739680600745778
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
Puro,DonaldG
中科院分区：
文献类型：
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作者：
Wu,DavidM;Minami,Masahiro;Kawamura,Hajime;Puro,DonaldG
目的：对含有周细胞的视网膜微血管的电紧张性结构知之甚少。在这里，作者专注于细胞到细胞的超极化传输，这可以诱导腔周细胞放松和管腔dilate.Methods：与穿孔贴片移液器，作者监测膜电位和离子电流对周细胞位于新鲜分离的大鼠视网膜微血管。电压的变化引起的管理电刺激到周细胞，miniprefusing的KATP通道开放剂pinacidil，或使用oxotremorine激活chloride channels.Results：暗示广泛的细胞间通讯，自发电压变化是惊人的相似，在广泛分离的周细胞。此外，电流注入一对采样的周细胞之一总是引起另一个采样的周细胞的电压响应;差距结解偶联剂庚醇阻断了这种传输。在双重记录中，从电流注入的周细胞传播的超极化在100 μ m内衰减了约40%。相比之下，在100 μ m处，吡那地尔诱导的超极化仅减少了0.2%。去极化也出现传播类似的transmission efficiency.Conclusions：基于实验，作者提出，视网膜微血管的电紧张性架构的关键特征包括高效的内皮细胞内的细胞间通信和相对低效的传输在周细胞/内皮连接。因此，内皮可能提供有效的途径，其功能性地连接收缩性周细胞，从而用于协调视网膜毛细血管的血管反应。
Objective:Little is known about the electrotonic architecture of the pericyte-containing retinal microvasculature. Here, the authors focus on the cell-to-cell transmission of hyperpolarization, which can induce abluminal pericytes to relax and lumens to dilate.Methods:With perforated-patch pipettes, the authors monitored the membrane potentials and ionic currents of pairs of pericytes located on freshly isolated rat retinal microvessels. Voltage changes were induced by administering electrical stimuli into pericytes, miniperfusing the KATPchannel opener pinacidil, or using oxotremorine to activate chloride channels.Results:Suggestive of extensive cell-to-cell communication, spontaneous voltage changes were strikingly similar in widely separated pericytes. In addition, injection of current into one of a pair of sampled pericytes always elicited a voltage response in the other sampled pericyte; the gap junction uncoupler, heptanol, blocked this transmission. In the dual recordings, hyperpolarization spreading from a current-injected pericyte decayed ∼40% within 100 μ m. In contrast, pinacidil-induced hyperpolarizations diminished by only ∼ 2% in 100 μ m. Depolarizations also appeared to spread with similar transmission efficacies.Conclusions:Based on the experiments, the authors propose that key features of the electrotonic architecture of retinal microvessels include highly efficient cell-to-cell communication within the endothelium and relatively inefficient transmission at pericyte/endothelial junctions. Thus, the endothelium is likely to provide an efficient pathway that functionally links contractile pericytes and thereby, serves to coordinate the vasomotor response of a retinal capillary.