Baxter B T, McGee G S, Shively V P, Drummond I A, Dixit S N, Yamauchi M, Pearce W H
Department of Surgery, Northwestern University School of Medicine, Chicago, Ill.
J Vasc Surg. 1992 Aug;16(2):192-200.
Although elastin depletion is thought to be an etiologic factor in abdominal aortic aneurysm, little is known about its transcription and posttranslational modification in normal and diseased human aorta. Our objectives were to quantify total elastin and elastin cross-links (desmosine/isodesmosine [DID]) and to determine if elastin mRNA was detectable in the disease-prone infrarenal aorta from patients with abdominal aortic aneurysm and a comparative group with no aneurysmal diseases. After preliminary extraction and thermolysin digestion, content of DID and the elastin tetrapeptide, valine-alanine-proline-glycine (VAPG), were determined by high-performance liquid chromatography. Tissue mRNA was studied by Northern blot analysis. Mean values (+/- SE) were compared by Student's t test. The proportion of insoluble elastin was markedly decreased in abdominal aortic aneurysm tissue (1.3% +/- 0.04% vs 12% +/- -2.8%; p less than 0.001). There was no difference in the small percentage of elastin solubilized during extraction in abdominal aortic aneurysm (5.3% +/- 1%) and no aneurysmal disease (6.0% +/- 1.2%; p = 0.71) tissues. The DID concentration of insoluble elastin was not different for abdominal aortic aneurysm and no aneurysmal disease tissue (0.18% +/- 0.07 vs 0.18 +/- 0.05 nm DID/nm VAPG; p = 0.97). On the basis of VAPG content, only 26% +/- 4% of the sodium hydroxide insoluble residue from abdominal aortic aneurysm was elastin; the predominate protein(s) was high in polar amino acids. Elastin mRNA was detectable in all tissues.(ABSTRACT TRUNCATED AT 250 WORDS)
尽管弹性蛋白耗竭被认为是腹主动脉瘤的一个病因，但对于其在正常和患病的人体主动脉中的转录及翻译后修饰却知之甚少。我们的目标是量化总弹性蛋白和弹性蛋白交联物（锁链素/异锁链素[DID]），并确定在腹主动脉瘤患者以及无动脉瘤疾病的对照组的易患疾病的肾下腹主动脉中是否可检测到弹性蛋白mRNA。经过初步提取和嗜热菌蛋白酶消化后，通过高效液相色谱法测定DID和弹性蛋白四肽缬氨酸-丙氨酸-脯氨酸-甘氨酸（VAPG）的含量。通过Northern印迹分析研究组织mRNA。采用学生t检验比较平均值（±标准误）。腹主动脉瘤组织中不溶性弹性蛋白的比例显著降低（1.3%±0.04%对12%±2.8%；p<0.001）。腹主动脉瘤组织（5.3%±1%）和无动脉瘤疾病组织（6.0%±1.2%；p = 0.71）在提取过程中溶解的弹性蛋白的小百分比没有差异。腹主动脉瘤组织和无动脉瘤疾病组织的不溶性弹性蛋白的DID浓度没有差异（0.18%±0.07对0.18±0.05 nm DID/nm VAPG；p = 0.97）。基于VAPG含量，腹主动脉瘤的氢氧化钠不溶性残渣中只有26%±4%是弹性蛋白；主要蛋白质富含极性氨基酸。在所有组织中均可检测到弹性蛋白mRNA。（摘要截短于250字）
