Sakai N, Tabb T, Garfield R E
Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston 77555-1062.
Am J Obstet Gynecol. 1992 Nov;167(5):1267-77. doi: 10.1016/s0002-9378(11)91699-8.
The aim of this study was to assess the presence and the permeability of gap junctions between human uterine smooth-muscle cells in culture.
The uterine smooth muscles obtained from term-pregnant women were cultured. The presence of gap junction was evaluated by immunocytochemistry with gap junction protein antibodies and by measuring input resistance and intercellular spread of lucifer yellow. These measures also evaluated the permeability of gap junctions. Octanol, isoproterenol, dibutyryl cyclic adenosine monophosphate and forskolin were applied to the cultures to assess their effects on the permeability of gap junctions.
During culture, immunocytochemical staining of gap junction protein (connexin 43) was increased and input resistance was decreased on day 2 of culture versus day 21 (18.4 +/- 7.87 M omega day 2; 3.8 +/- 1.76 M omega, day 21; p < 0.001). However, the decrease in input resistance was related to cell density rather than time in culture (16.4 +/- 5.01 M omega, single cells on days 1 and 2; 5.3 +/- 2.35 M omega, high-density cultures on days 1 and 2; p < 0.001). Octanol increased input resistance and intercellular spread of lucifer yellow in confluent cultures; isoproterenol, dibutyryl cyclic adenosine monophosphate, and forskolin did not.
The increased staining of connexin 43 and the decreased input resistance during culture are evidence of elevated number of gap junctions between cells. The rapid and reversible increase in input resistance and decrease in spread of lucifer yellow by octanol are the result of decreased permeability of gap junctions. These two methods of modulation of gap junctions in human uterine smooth muscles are thought to be major mechanisms for the control of uterine contractility.
本研究旨在评估培养的人子宫平滑肌细胞间缝隙连接的存在情况及其通透性。
取自足月孕妇的子宫平滑肌进行培养。通过使用缝隙连接蛋白抗体进行免疫细胞化学以及测量输入电阻和荧光黄的细胞间扩散来评估缝隙连接的存在情况。这些方法也用于评估缝隙连接的通透性。向培养物中加入辛醇、异丙肾上腺素、二丁酰环磷酸腺苷和福斯高林，以评估它们对缝隙连接通透性的影响。
在培养过程中，与第21天相比，培养第2天缝隙连接蛋白（连接蛋白43）的免疫细胞化学染色增加，输入电阻降低（第2天为18.4±7.87 MΩ；第21天为3.8±1.76 MΩ；p<0.001）。然而，输入电阻的降低与细胞密度有关，而非培养时间（第1天和第2天单细胞时为16.4±5.01 MΩ；第1天和第2天高细胞密度培养时为5.3±2.35 MΩ；p<0.001）。辛醇增加了汇合培养物中的输入电阻和荧光黄的细胞间扩散；而异丙肾上腺素、二丁酰环磷酸腺苷和福斯高林则没有。
培养过程中连接蛋白43染色增加和输入电阻降低证明细胞间缝隙连接数量增加。辛醇使输入电阻快速可逆增加以及荧光黄扩散减少是缝隙连接通透性降低的结果。这两种调节人子宫平滑肌细胞间缝隙连接的方法被认为是控制子宫收缩力的主要机制。
