Lewis W, Sadeghi A M, Laks H, Drinkwater D C, Asai Y, Hall T L, Gonzalez B
Department of Pathology, UCLA School of Medicine 90024.
J Heart Lung Transplant. 1991 Jan-Feb;10(1 Pt 1):92-9.
Adult rats underwent surgical placement of heterotopic cardiac isografts. From 14 to 60 days postoperatively, native heart and transplanted heart protein synthesis was determined. Right ventricle and left ventricle free walls from native and transplanted hearts were dissected, minced into cubes, and incubated in medium containing sulfur-35 methionine. Tissue was harvested, washed, and homogenized in buffer and fractionated centrifugally. Specific radioactivity of polypeptides from transplant isograft right and left ventricle fractions were 6.36 +/- 5.1 and 4.93 +/- 3.6 (mean +/- SD, x 10(-6) cpm/mg protein), respectively. In contrast, native isograft right and left ventricle specific radioactivity was 1.71 +/- 1.49 and 1.07 +/- 0.88 (mean +/- SD, x 10(-6) cpm/mg protein), respectively. Autoradiograms of two-dimensional electrophoretograms revealed increased radiodensity of resolved polypeptides from transplanted and native hearts, which comigrated with nonsarcomeric (beta, gamma) actins. Skeletin and tubulin were prominent on one-and two-dimensional autoradiograms from 14 to 60 days. Radiolabeling of alpha actin polypeptide maximized at 14 days and was found to decrease at 30 and 60 days in comparison with nonsarcomeric actin isoforms. Correlative myocardial microscopic sections showed no fiber hypertrophy, but fiber atrophy was found. Results suggest a relative increase in polypeptide synthesis in the heterotopic transplanted heart samples.
成年大鼠接受了异位心脏同基因移植手术。术后14至60天，测定了自体心脏和移植心脏的蛋白质合成情况。从自体心脏和移植心脏中分离出右心室和左心室游离壁，切成小块，置于含有硫-35蛋氨酸的培养基中孵育。收集组织，洗涤后在缓冲液中匀浆，然后进行离心分级分离。移植同基因移植物右心室和左心室组分中多肽的比放射性分别为6.36±5.1和4.93±3.6（平均值±标准差，×10⁻⁶ cpm/mg蛋白质）。相比之下，自体同基因移植物右心室和左心室的比放射性分别为1.71±1.49和1.07±0.88（平均值±标准差，×10⁻⁶ cpm/mg蛋白质）。二维电泳图谱的放射自显影片显示，来自移植心脏和自体心脏的已分离多肽的放射密度增加，这些多肽与非肌节（β、γ）肌动蛋白共迁移。在术后14至60天的一维和二维放射自显影片上，骨架蛋白和微管蛋白很突出。与非肌节肌动蛋白异构体相比，α肌动蛋白多肽的放射性标记在14天时达到最大值，在30天和60天时下降。相关的心肌显微切片未显示纤维肥大，但发现了纤维萎缩。结果表明，异位移植心脏样本中的多肽合成相对增加。
