Relative distribution of three major lactate transporters in frozen human tissues and their localization in unfixed skeletal muscle
Relative distribution of three major lactate transporters in frozen human tissues and their localization in unfixed skeletal muscle
复制标题
DOI：
10.1002/mus.10168
复制
发表时间：
2002-07-01
期刊：
影响因子：
3.4
通讯作者：
Foellmer, JW
中科院分区：
文献类型：
--
作者：
Fishbein, WN;Merezhinskaya, N;Foellmer, JW
我们已经制备了亲和纯化的兔多克隆抗体的近C端肽的人单羧酸转运蛋白（MCT）1，2和4耦合到匙孔血蓝蛋白。每种抗血清只与其特异性肽抗原反应，并在十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）的组织膜蛋白的Western印迹上进行化学发光反应后，产生一条不同的分子量条带（通过与抗原预孵育阻断）。密度测定显示，在一组15个冷冻人体组织中，每种MCT的表达模式不同，分布为MCT 1>> MCT 2> MCT 4。使用荧光素偶联二抗的未固定骨骼肌的荧光显微镜检查与反向腺苷三磷酸酶（ATP酶）染色的连续切片相关，以确定纤维类型定位。MCT 1在I型纤维的肌膜中表达较高，在2a型纤维中表达中等至较低，在2b型纤维中几乎不表达。相比之下，MCT 4表达在大多数1型纤维的膜中低至不存在，但在大多数2a和所有2b纤维中高，这支持了这样的观点，即它们在工作期间的高乳酸水平可能部分地被引导到邻近的1型（可能还有2a）纤维用于氧化，从而延迟疲劳。MCT 2表达仅限于1型纤维亚群的肌膜，其变化范围为：
We have prepared affinity-purified rabbit polyclonal antibodies to the near-C-terminal peptides of human monocarboxylate transporters (MCTs) 1, 2, and 4 coupled to keyhole limpet hemocyanin. Each antiserum reacted only with its specific peptide antigen and gave a distinct molecular weight band (blocked by preincubation with antigen) after chemiluminescence reaction on Western blots from sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of tissue membrane proteins. Densitometry showed distinctive expression patterns for each MCT in a panel of 15 frozen human tissues, with the distribution of MCT1 >>MCT2>MCT4. Fluorescence microscopy of unfixed skeletal muscle using fluorescein-conjugated secondary antibody was correlated with reverse adenosine triphosphatase (ATPase) stained sequential sections to identify fiber-type localization. MCT1 expression was high in the sarcolemma of type I fibers, modest to low in type 2a fibers, and almost absent in type 2b fibers. In contrast, MCT4 expression was low to absent in the membrane of most type 1 fibers, but high in most 2a and in all 2b fibers, favoring the view that their high lactate levels during work may be channeled in part to neighboring type 1 (and perhaps 2a) fibers for oxidation, thereby delaying fatigue. MCT2 expression was limited to the sarcolemma of a type 1 fiber subset, which varied from