Specific binding of leukotriene C4 to ileal segments and subcellular fractions of ileal smooth muscle cells.
Specific binding of leukotriene C4 to ileal segments and subcellular fractions of ileal smooth muscle cells.
复制标题
白三烯 C4 与回肠平滑肌细胞的回肠段和亚细胞部分特异性结合。
DOI：
10.1073/pnas.81.14.4529
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发表时间：
1984
影响因子：
11.1
通讯作者：
Austen,KF
中科院分区：
文献类型：
--
作者：
Krilis,S;Lewis,RA;Corey,EJ;Austen,KF
一个特定的高亲和力受体白三烯C4（LTC 4）已被确定的部分从豚鼠回肠的纵向平滑肌，在破碎的细胞从回肠段，并在亚细胞组分富集线粒体膜和质膜，分别。4 ℃下固定输入下的特异性[3 H] LTC 4结合在60 min时达到平台期，并且在通过引入过量未标记的同源配体达到结合平衡后大于80%可逆。配体分析表明，一个单一的高亲和力受体上的平滑肌段，破碎的细胞，和亚细胞级分富集线粒体膜和质膜的Kd值分别为7.6 nM，1.3 nM，13 nM，和8.5 nM。这些Kd值与已知在回肠肌中引起痉挛性反应的LTC 4浓度重叠，表明放射性配体识别介导生物反应的受体。用固定输入的LTC 4放射性配体和递增浓度的天然硫肽白三烯与破坏的回肠细胞和亚细胞级分的竞争分析表明，白三烯D4（LTD 4）的活性比LTC 4低1-3 μ m，而白三烯E4（LTE 4）基本上无活性。因此，回肠纵向平滑肌细胞具有对LTC 4具有选择性的高亲和力受体，并且该受体表现出质膜和亚细胞分布。
A specific high-affinity receptor for leukotriene C4 (LTC4) has been identified on segments of longitudinal smooth muscle from guinea pig ileum, in disrupted cells obtained from the ileal segments, and in subcellular fractions enriched for mitochondrial membranes and plasma membranes, respectively. Specific [3H]LTC4 binding at a fixed input at 4 degrees C reached a plateau at 60 min with each of the four preparations and was greater than 80% reversible after binding reached equilibrium by the introduction of excess unlabeled homoligand. LIGAND analysis demonstrated a single high-affinity receptor on the smooth muscle segments, the disrupted cells, and the subcellular fractions enriched for mitochondrial membranes and for plasma membranes with respective Kd values of 7.6 nM, 1.3 nM, 13 nM, and 8.5 nM. These Kd values overlap with the concentration of LTC4 known to elicit a spasmogenic response in the ileal muscle, indicating that the radioligand recognizes a receptor that mediates the biological response. Competition analysis with disrupted ileal cells and subcellular fractions with a fixed input of LTC4 radioligand and incremental concentrations of the natural sulfidopeptide leukotrienes demonstrated leukotriene D4 (LTD4) to be 1-3 logarithms less active than LTC4 and leukotriene E4 (LTE4) to be essentially inactive. Thus, ileal longitudinal smooth muscle cells possess a high-affinity receptor that is selective for LTC4 and that receptor exhibits both a plasma membrane and subcellular distribution.