Gap junction dynamics: reversible effects of hydrogen ions
Gap junction dynamics: reversible effects of hydrogen ions
复制标题
间隙连接动力学：氢离子的可逆效应
DOI：
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发表时间：
1980
影响因子：
7.8
通讯作者：
L. L. Peracchia
中科院分区：
文献类型：
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作者：
C. Peracchia;L. L. Peracchia
通过暴露于3 × 10（-7）M或更高[H+]（pH 6.5或更低），在从小牛透镜纤维分离的间隙连接中诱导膜内颗粒填充物的可逆结晶。由低pH值引起的从无序到结晶颗粒包装的变化类似于通过解偶联处理在完整细胞的连接处产生的那些，这表明H+，像二价阳离子，可以是解偶联剂。对照和低pH值处理的间隙连接的冷冻断裂外观未被戊二醛固定和冷冻保护处理改变，如根据Heuser等人（13）的实验所示，在该实验中，完整细胞和分离部分的间隙连接在快速冷冻至液氮温度后冷冻断裂。在暴露于低pH值的结中，颗粒通常形成正交和菱形阵列，经常彼此融合。这些阵列的许多结构特征表明，透镜纤维间隙连接的颗粒可以被成形为四聚体。
Reversible crystallization of intramembrane particle packings is induced in gap junctions isolated from calf lens fibers by exposure to 3 x 10(-7) M or higher [H+] (pH 6.5 or lower). The changes from disordered to crystalline particle packings induced by low pH are similar to those produced in junctions of intact cells by uncoupling treatments, indicating that H+, like divalent cations, could be an uncoupling agent. The freeze-fracture appearance of both control and low pH-treated gap junctions is not altered by glutaraldehyde fixation and cryoprotective treatment, as suggested by experiments in which gap junctions of both intact cells and isolated fractions are freeze- fractured after rapid freezing to liquid N2 temperature according to Heuser et al. (13). In junctions exposed to low pH, the particles most often form orthogonal and rhombic arrays, frequently fused with each other. A number of structural characteristics of these arrays suggest that the particles of lens fiber gap junctions may be shaped as tetrameres.